diff --git a/aard.cc b/aard.cc
index 2505aeaa..ac1963f6 100644
--- a/aard.cc
+++ b/aard.cc
@@ -29,6 +29,7 @@
 
 #include "ufile.hh"
 #include "wstring_qt.hh"
+#include "qt4x5.hh"
 
 namespace Aard {
 
@@ -594,7 +595,7 @@ void AardArticleRequestRunnable::run()
 
 void AardArticleRequest::run()
 {
-  if ( isCancelled )
+  if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
   {
     finish();
     return;
@@ -621,7 +622,7 @@ void AardArticleRequest::run()
 
   for( unsigned x = 0; x < chain.size(); ++x )
   {
-    if ( isCancelled )
+    if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
     {
       finish();
       return;
diff --git a/about.cc b/about.cc
index e784ed82..800c7b12 100644
--- a/about.cc
+++ b/about.cc
@@ -4,6 +4,8 @@
 #include "about.hh"
 #include <QtGui>
 
+#include "qt4x5.hh"
+
 About::About( QWidget * parent ): QDialog( parent )
 {
   ui.setupUi( this );
@@ -39,7 +41,7 @@ About::About( QWidget * parent ): QDialog( parent )
 
       str.replace( "\\", "@" );
 
-      str = Qt::escape( str );
+      str = Qt4x5::escape( str );
 
       int colon = str.indexOf( ":" );
 
diff --git a/article_netmgr.cc b/article_netmgr.cc
index 9902c818..7fab6e49 100644
--- a/article_netmgr.cc
+++ b/article_netmgr.cc
@@ -10,6 +10,8 @@
 #include "article_netmgr.hh"
 #include "wstring_qt.hh"
 #include "dprintf.hh"
+#include "qt4x5.hh"
+
 using std::string;
 
 namespace
@@ -134,24 +136,24 @@ sptr< Dictionary::DataRequest > ArticleNetworkAccessManager::getResource(
   {
     contentType = "text/html";
 
-    if ( url.queryItemValue( "blank" ) == "1" )
+    if ( Qt4x5::Url::queryItemValue( url, "blank" ) == "1" )
       return articleMaker.makeEmptyPage();
 
     bool groupIsValid = false;
 
-    QString word = url.queryItemValue( "word" );
-    unsigned group = url.queryItemValue( "group" ).toUInt( &groupIsValid );
+    QString word = Qt4x5::Url::queryItemValue( url, "word" );
+    unsigned group = Qt4x5::Url::queryItemValue( url, "group" ).toUInt( &groupIsValid );
 
     // See if we have some dictionaries muted
 
     QSet< QString > mutedDicts =
-        QSet< QString >::fromList( url.queryItemValue( "muted" ).split( ',' ) );
+        QSet< QString >::fromList( Qt4x5::Url::queryItemValue( url, "muted" ).split( ',' ) );
 
     // Unpack contexts
 
     QMap< QString, QString > contexts;
 
-    QString contextsEncoded = url.queryItemValue( "contexts" );
+    QString contextsEncoded = Qt4x5::Url::queryItemValue( url, "contexts" );
 
     if ( contextsEncoded.size() )
     {
diff --git a/articleview.cc b/articleview.cc
index 93e77009..59ec808e 100644
--- a/articleview.cc
+++ b/articleview.cc
@@ -12,15 +12,16 @@
 #include <QClipboard>
 #include <QKeyEvent>
 #include <QFileDialog>
+#include <QDebug>
+#include <QWebElement>
+#include <QCryptographicHash>
 #include "folding.hh"
 #include "wstring_qt.hh"
 #include "webmultimediadownload.hh"
 #include "programs.hh"
 #include "dprintf.hh"
 #include "ffmpegaudio.hh"
-#include <QDebug>
-#include <QWebElement>
-#include <QCryptographicHash>
+#include "qt4x5.hh"
 
 #include <assert.h>
 
@@ -200,11 +201,11 @@ void ArticleView::showDefinition( QString const & word, unsigned group,
 
   req.setScheme( "gdlookup" );
   req.setHost( "localhost" );
-  req.addQueryItem( "word", word );
-  req.addQueryItem( "group", QString::number( group ) );
+  Qt4x5::Url::addQueryItem( req, "word", word );
+  Qt4x5::Url::addQueryItem( req, "group", QString::number( group ) );
 
   if ( scrollTo.size() )
-    req.addQueryItem( "scrollto", scrollTo );
+    Qt4x5::Url::addQueryItem( req, "scrollto", scrollTo );
 
   if ( contexts.size() )
   {
@@ -218,13 +219,13 @@ void ArticleView::showDefinition( QString const & word, unsigned group,
 
     buf.close();
 
-    req.addQueryItem( "contexts", QString::fromLatin1( buf.buffer().toBase64() ) );
+    Qt4x5::Url::addQueryItem( req,  "contexts", QString::fromLatin1( buf.buffer().toBase64() ) );
   }
 
   QString mutedDicts = getMutedForGroup( group );
 
   if ( mutedDicts.size() )
-    req.addQueryItem( "muted", mutedDicts );
+    Qt4x5::Url::addQueryItem( req,  "muted", mutedDicts );
 
   // Update both histories (pages history and headwords history)
   saveHistoryUserData();
@@ -325,11 +326,11 @@ void ArticleView::loadFinished( bool )
     }
   }
   else
-  if ( url.queryItemValue( "scrollto" ).startsWith( "gdfrom-" ) )
+  if ( Qt4x5::Url::queryItemValue( url, "scrollto" ).startsWith( "gdfrom-" ) )
   {
     // There is no active article saved in history, but we have it as a parameter.
     // setCurrentArticle will save it and scroll there.
-    setCurrentArticle( url.queryItemValue( "scrollto" ), true );
+    setCurrentArticle( Qt4x5::Url::queryItemValue( url, "scrollto" ), true );
   }
 
 
@@ -375,8 +376,8 @@ void ArticleView::handleUrlChanged( QUrl const & url )
 
 unsigned ArticleView::getGroup( QUrl const & url )
 {
-  if ( url.scheme() == "gdlookup" && url.hasQueryItem( "group" ) )
-    return url.queryItemValue( "group" ).toUInt();
+  if ( url.scheme() == "gdlookup" && Qt4x5::Url::hasQueryItem( url, "group" ) )
+    return Qt4x5::Url::queryItemValue( url, "group" ).toUInt();
 
   return 0;
 }
@@ -693,10 +694,10 @@ void ArticleView::linkHovered ( const QString & link, const QString & , const QS
       def = def.mid( 1 );
     }
 
-    if( url.hasQueryItem( "dict" ) )
+    if( Qt4x5::Url::hasQueryItem( url, "dict" ) )
     {
       // Link to other dictionary
-      QString dictName( url.queryItemValue( "dict" ) );
+      QString dictName( Qt4x5::Url::queryItemValue( url, "dict" ) );
       if( !dictName.isEmpty() )
         msg = tr( "Definition from dictionary \"%1\": %2" ).arg( dictName ).arg( def );
     }
@@ -763,10 +764,10 @@ void ArticleView::openLink( QUrl const & url, QUrl const & ref,
     else
     {
       QString newScrollTo( scrollTo );
-      if( url.hasQueryItem( "dict" ) )
+      if( Qt4x5::Url::hasQueryItem( url, "dict" ) )
       {
         // Link to other dictionary
-        QString dictName( url.queryItemValue( "dict" ) );
+        QString dictName( Qt4x5::Url::queryItemValue( url, "dict" ) );
         for( unsigned i = 0; i < allDictionaries.size(); i++ )
         {
           if( dictName.compare( QString::fromUtf8( allDictionaries[ i ]->getName().c_str() ) ) == 0 )
@@ -938,7 +939,7 @@ void ArticleView::openLink( QUrl const & url, QUrl const & ref,
 // TODO: Port TTS
 #if defined( Q_OS_WIN32 ) || defined( Q_OS_MACX )
     // Text to speech
-    QString md5Id = url.queryItemValue( "engine" );
+    QString md5Id = Qt4x5::Url::queryItemValue( url, "engine" );
     QString text( url.path().mid( 1 ) );
 
     for ( Config::VoiceEngines::const_iterator i = cfg.voiceEngines.begin();
@@ -1054,14 +1055,14 @@ void ArticleView::updateMutedContents()
 
   QString mutedDicts = getMutedForGroup( group );
 
-  if ( currentUrl.queryItemValue( "muted" ) != mutedDicts )
+  if ( Qt4x5::Url::queryItemValue( currentUrl, "muted" ) != mutedDicts )
   {
     // The list has changed -- update the url
 
-    currentUrl.removeQueryItem( "muted" );
+    Qt4x5::Url::removeQueryItem( currentUrl, "muted" );
 
     if ( mutedDicts.size() )
-    currentUrl.addQueryItem( "muted", mutedDicts );
+    Qt4x5::Url::addQueryItem( currentUrl, "muted", mutedDicts );
 
     saveHistoryUserData();
 
diff --git a/bgl.cc b/bgl.cc
index 00acb070..54ea9b37 100644
--- a/bgl.cc
+++ b/bgl.cc
@@ -31,6 +31,8 @@
 
 #include <QRegExp>
 
+#include "qt4x5.hh"
+
 namespace Bgl {
 
 using std::map;
@@ -472,7 +474,7 @@ void BglHeadwordsRequestRunnable::run()
 
 void BglHeadwordsRequest::run()
 {
-  if ( isCancelled )
+  if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
   {
     finish();
     return;
@@ -484,7 +486,7 @@ void BglHeadwordsRequest::run()
 
   for( unsigned x = 0; x < chain.size(); ++x )
   {
-    if ( isCancelled )
+    if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
     {
       finish();
       return;
@@ -657,7 +659,7 @@ void BglArticleRequest::fixHebArticle(string & hebArticle) // Hebrew support - r
 
 void BglArticleRequest::run()
 {
-  if ( isCancelled )
+  if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
   {
     finish();
     return;
@@ -689,7 +691,7 @@ void BglArticleRequest::run()
 
   for( unsigned x = 0; x < chain.size(); ++x )
   {
-    if ( isCancelled )
+    if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
     {
       finish();
       return;
@@ -909,7 +911,7 @@ void BglResourceRequestRunnable::run()
 
 void BglResourceRequest::run()
 {
-  if ( isCancelled )
+  if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
   {
     finish();
     return;
@@ -927,7 +929,7 @@ void BglResourceRequest::run()
 
   for( size_t count = resourcesCount; count--; )
   {
-    if ( isCancelled )
+    if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
       break;
 
     vector< char > nameData( idx.read< uint32_t >() );
diff --git a/btreeidx.cc b/btreeidx.cc
index 5806ba20..edfbb40b 100644
--- a/btreeidx.cc
+++ b/btreeidx.cc
@@ -11,6 +11,7 @@
 #include <string.h>
 #include <stdlib.h>
 #include "dprintf.hh"
+#include "qt4x5.hh"
 
 //#define __BTREE_USE_LZO
 // LZO mode is experimental and unsupported. Tests didn't show any substantial
@@ -178,7 +179,7 @@ void BtreeWordSearchRunnable::run()
 
 void BtreeWordSearchRequest::run()
 {
-  if ( isCancelled )
+  if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
   {
     finish();
     return;
@@ -225,7 +226,7 @@ void BtreeWordSearchRequest::run()
     if ( chainOffset )
     for( ; ; )
     {
-      if ( isCancelled )
+      if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
         break;
       
       //DPRINTF( "offset = %u, size = %u\n", chainOffset - &leaf.front(), leaf.size() );
@@ -296,7 +297,7 @@ void BtreeWordSearchRequest::run()
       }
     }
 
-    if ( charsLeftToChop && !isCancelled )
+    if ( charsLeftToChop && !Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
     {
       --charsLeftToChop;
       folded.resize( folded.size() - 1 );
diff --git a/dictionary.cc b/dictionary.cc
index f5f3b94c..3446065d 100644
--- a/dictionary.cc
+++ b/dictionary.cc
@@ -23,22 +23,24 @@
 #include <QPainter>
 #include <QRegExp>
 
+#include "qt4x5.hh"
+
 namespace Dictionary {
 
 bool Request::isFinished()
 {
-  return (int)isFinishedFlag;
+  return Qt4x5::AtomicInt::loadAcquire( isFinishedFlag );
 }
 
 void Request::update()
 {
-  if ( !isFinishedFlag )
+  if ( !Qt4x5::AtomicInt::loadAcquire( isFinishedFlag ) )
     emit updated();
 }
 
 void Request::finish()
 {
-  if ( !isFinishedFlag )
+  if ( !Qt4x5::AtomicInt::loadAcquire( isFinishedFlag ) )
   {
     isFinishedFlag.ref();
 
diff --git a/dsl.cc b/dsl.cc
index a7a9b7c6..36af633b 100644
--- a/dsl.cc
+++ b/dsl.cc
@@ -48,6 +48,8 @@
 // For SVG handling
 #include <QtSvg/QSvgRenderer>
 
+#include "qt4x5.hh"
+
 namespace Dsl {
 
 using namespace Details;
@@ -301,11 +303,11 @@ public:
 
 void DslDictionary::deferredInit()
 {
-  if ( !deferredInitDone )
+  if ( !Qt4x5::AtomicInt::loadAcquire( deferredInitDone ) )
   {
     Mutex::Lock _( deferredInitMutex );
 
-    if ( deferredInitDone )
+    if ( Qt4x5::AtomicInt::loadAcquire( deferredInitDone ) )
       return;
 
     if ( !deferredInitRunnableStarted )
@@ -329,11 +331,11 @@ string const & DslDictionary::ensureInitDone()
 
 void DslDictionary::doDeferredInit()
 {
-  if ( !deferredInitDone )
+  if ( !Qt4x5::AtomicInt::loadAcquire( deferredInitDone ) )
   {
     Mutex::Lock _( deferredInitMutex );
 
-    if ( deferredInitDone )
+    if ( Qt4x5::AtomicInt::loadAcquire( deferredInitDone ) )
       return;
 
     // Do deferred init
@@ -950,7 +952,7 @@ string DslDictionary::nodeToHtml( ArticleDom::Node const & node )
       {
         QList< QPair< QString, QString > > query;
         query.append( QPair< QString, QString >( attr.left( n ), attr.mid( n + 1 ) ) );
-        url.setQueryItems( query );
+        Qt4x5::Url::setQueryItems( url, query );
       }
     }
 
@@ -1162,7 +1164,7 @@ void DslArticleRequestRunnable::run()
 
 void DslArticleRequest::run()
 {
-  if ( isCancelled )
+  if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
   {
     finish();
     return;
@@ -1197,7 +1199,7 @@ void DslArticleRequest::run()
   for( unsigned x = 0; x < chain.size(); ++x )
   {
     // Check if we're cancelled occasionally
-    if ( isCancelled )
+    if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
     {
       finish();
       return;
@@ -1347,7 +1349,7 @@ void DslResourceRequestRunnable::run()
 void DslResourceRequest::run()
 {
   // Some runnables linger enough that they are cancelled before they start
-  if ( isCancelled )
+  if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
   {
     finish();
     return;
diff --git a/ffmpegaudio.cc b/ffmpegaudio.cc
index ca0bb195..3ddb7164 100644
--- a/ffmpegaudio.cc
+++ b/ffmpegaudio.cc
@@ -24,6 +24,8 @@ extern "C" {
 
 #include <vector>
 
+#include "qt4x5.hh"
+
 using std::vector;
 
 namespace Ffmpeg
@@ -336,13 +338,14 @@ bool DecoderContext::play( QString & errorString )
   AVPacket packet;
   av_init_packet( &packet );
 
-  while ( !isCancelled_ && av_read_frame( formatContext_, &packet ) >= 0 )
+  while ( !Qt4x5::AtomicInt::loadAcquire( isCancelled_ ) &&
+          av_read_frame( formatContext_, &packet ) >= 0 )
   {
     if ( packet.stream_index == audioStream_->index )
     {
       int gotFrame = 0;
       avcodec_decode_audio4( codecContext_, frame, &gotFrame, &packet );
-      if ( !isCancelled_ && gotFrame )
+      if ( !Qt4x5::AtomicInt::loadAcquire( isCancelled_ ) && gotFrame )
       {
         playFrame( frame );
       }
@@ -351,13 +354,14 @@ bool DecoderContext::play( QString & errorString )
     av_free_packet( &packet );
   }
 
-  if ( !isCancelled_ && codecContext_->codec->capabilities & CODEC_CAP_DELAY )
+  if ( !Qt4x5::AtomicInt::loadAcquire( isCancelled_ ) &&
+       codecContext_->codec->capabilities & CODEC_CAP_DELAY )
   {
     av_init_packet( &packet );
     int gotFrame = 0;
     while ( avcodec_decode_audio4( codecContext_, frame, &gotFrame, &packet ) >= 0 && gotFrame )
     {
-      if ( isCancelled_ )
+      if ( Qt4x5::AtomicInt::loadAcquire( isCancelled_ ) )
         break;
       playFrame( frame );
     }
@@ -536,7 +540,7 @@ void DecoderThread::run()
 
   while ( !deviceMutex_.tryLock( 100 ) )
   {
-    if ( isCancelled_ )
+    if ( Qt4x5::AtomicInt::loadAcquire( isCancelled_ ) )
       return;
   }
 
diff --git a/goldendict.pro b/goldendict.pro
index 8653a234..6871b9a6 100644
--- a/goldendict.pro
+++ b/goldendict.pro
@@ -19,10 +19,21 @@ isEmpty( hasGit ) {
 
 # DEPENDPATH += . generators
 INCLUDEPATH += .
-QT += webkit
-QT += xml
-QT += network
-QT += svg
+
+QT += core \
+      gui \
+      xml \
+      network \
+      svg
+
+greaterThan(QT_MAJOR_VERSION, 4) {
+    QT += widgets \
+          webkitwidgets \
+          printsupport
+} else {
+    QT += webkit
+}
+
 CONFIG += exceptions \
     rtti \
     stl
@@ -46,11 +57,17 @@ win32 {
     LIBS += -lvorbisfile \
         -lvorbis \
         -logg \
-        -lhunspell-1.3.2 \
         -lao \
         -lavutil-gd \
         -lavformat-gd \
         -lavcodec-gd
+
+    greaterThan(QT_MAJOR_VERSION, 4) {
+      LIBS += -lhunspell-1.3
+    } else {
+      LIBS += -lhunspell-1.3.2
+    }
+
     RC_FILE = goldendict.rc
     INCLUDEPATH += winlibs/include
     LIBS += -L$${PWD}/winlibs/lib
@@ -236,7 +253,8 @@ HEADERS += folding.hh \
     mdx.hh \
     voiceengines.hh \
     ffmpegaudio.hh \
-    articleinspector.hh
+    articleinspector.hh \
+    qt4x5.hh
 
 FORMS += groups.ui \
     dictgroupwidget.ui \
@@ -411,12 +429,13 @@ TRANSLATIONS += locale/ru_RU.ts \
   QMAKE_EXTRA_TARGETS += revtarget
   PRE_TARGETDEPS      += $$PWD/version.txt
   revtarget.target     = $$PWD/version.txt
-!win32 {
-  revtarget.commands   = cd $$PWD; git describe --tags --always --dirty > $$revtarget.target
-}
-win32 {
-  revtarget.commands   = git --git-dir=\"$$PWD/.git\" describe --tags --always --dirty > $$revtarget.target
-}
+
+  !win32 {
+    revtarget.commands   = cd $$PWD; git describe --tags --always --dirty > $$revtarget.target
+  } else {
+    revtarget.commands   = git --git-dir=\"$$PWD/.git\" describe --tags --always --dirty > $$revtarget.target
+  }
+
   ALL_SOURCES = $$SOURCES $$HEADERS $$FORMS
   for(src, ALL_SOURCES) {
     QUALIFIED_SOURCES += $${PWD}/$${src}
diff --git a/groups_widgets.cc b/groups_widgets.cc
index 0548de06..8932e606 100644
--- a/groups_widgets.cc
+++ b/groups_widgets.cc
@@ -17,6 +17,8 @@
 #include <QMap>
 #include <QVector>
 #include <QFileInfo>
+#include <QFileDialog>
+#include <QMessageBox>
 
 using std::vector;
 
@@ -164,14 +166,16 @@ void DictListModel::populate(
   dictionaries = active;
   allDicts = &available;
 
-  reset();
+  beginResetModel();
+  endResetModel();
 }
 
 void DictListModel::populate(
   std::vector< sptr< Dictionary::Class > > const & active )
 {
   dictionaries = active;
-  reset();
+  beginResetModel();
+  endResetModel();
 }
 
 void DictListModel::setAsSource()
@@ -356,7 +360,8 @@ void DictListModel::removeSelectedRows( QItemSelectionModel * source )
     dictionaries.erase( dictionaries.begin() + rows.at( i ).row() );
   }
 
-  reset();
+  beginResetModel();
+  endResetModel();
   emit contentChanged();
 }
 
@@ -413,7 +418,8 @@ void DictListModel::addSelectedUniqueFromModel( QItemSelectionModel * source )
         list.remove( j );
         if ( list.isEmpty() )
         {
-          reset();
+          beginResetModel();
+          endResetModel();
           emit contentChanged();
           return;
         }
@@ -422,7 +428,8 @@ void DictListModel::addSelectedUniqueFromModel( QItemSelectionModel * source )
     }
   }
 
-  reset();
+  beginResetModel();
+  endResetModel();
   emit contentChanged();
 }
 
@@ -447,7 +454,8 @@ void DictListModel::filterDuplicates()
 
   if ( doReset )
   {
-    reset();
+    beginResetModel();
+    endResetModel();
     emit contentChanged();
   }
 }
diff --git a/historypanewidget.cc b/historypanewidget.cc
index 68687362..46f52001 100644
--- a/historypanewidget.cc
+++ b/historypanewidget.cc
@@ -254,5 +254,6 @@ void HistoryModel::historyChanged()
 {
 //  qDebug() << "History Changed!!";
 
-  reset();
+  beginResetModel();
+  endResetModel();
 }
diff --git a/hotkeywrapper.cc b/hotkeywrapper.cc
index 73404ff0..28939b0b 100644
--- a/hotkeywrapper.cc
+++ b/hotkeywrapper.cc
@@ -4,6 +4,10 @@
 #endif
 
 #include "hotkeywrapper.hh"
+
+#include <QWidget>
+#include <QMainWindow>
+
 #include "dprintf.hh"
 
 #ifdef Q_WS_X11
@@ -15,6 +19,9 @@
 QHotkeyApplication::QHotkeyApplication( int & argc, char ** argv ):
   QtSingleApplication( argc, argv )
 {
+#if defined( Q_OS_WIN ) && IS_QT_5
+  installNativeEventFilter( this );
+#endif
 }
 
 QHotkeyApplication::QHotkeyApplication( QString const & id,
@@ -201,7 +208,7 @@ bool HotkeyWrapper::checkState(quint32 vk, quint32 mod)
 
 //////////////////////////////////////////////////////////////////////////
 
-#ifdef Q_WS_WIN
+#ifdef Q_OS_WIN
 
 void HotkeyWrapper::init()
 {
@@ -332,6 +339,25 @@ void HotkeyWrapper::unregister()
 }
 
 
+#if IS_QT_5
+
+bool QHotkeyApplication::nativeEventFilter( const QByteArray & /*eventType*/, void * message, long * result )
+{
+  MSG * msg = reinterpret_cast< MSG * >( message );
+
+  if ( msg->message == WM_HOTKEY )
+  {
+    for (int i = 0; i < hotkeyWrappers.size(); i++)
+    {
+      if ( hotkeyWrappers.at(i)->winEvent( msg, result ) )
+        return true;
+    }
+  }
+
+  return false;
+}
+
+#else // IS_QT_5
 
 bool QHotkeyApplication::winEventFilter ( MSG * message, long * result )
 {
@@ -347,6 +373,8 @@ bool QHotkeyApplication::winEventFilter ( MSG * message, long * result )
   return QApplication::winEventFilter( message, result );
 }
 
+#endif
+
 //////////////////////////////////////////////////////////////////////////
 
 #else
diff --git a/hotkeywrapper.hh b/hotkeywrapper.hh
index 1e5a2669..8d3b112e 100644
--- a/hotkeywrapper.hh
+++ b/hotkeywrapper.hh
@@ -20,12 +20,13 @@
 
 #include "ex.hh"
 #include "qtsingleapplication.h"
+#include "qt4x5.hh"
 
 //////////////////////////////////////////////////////////////////////////
 
 struct HotkeyStruct
 {
-  HotkeyStruct() {};
+  HotkeyStruct() {}
   HotkeyStruct( quint32 key, quint32 key2, quint32 modifier, int handle, int id );
 
   quint32 key, key2;
@@ -187,6 +188,9 @@ public:
 };
 
 class QHotkeyApplication : public QtSingleApplication
+#if defined( Q_OS_WIN ) && IS_QT_5
+    , public QAbstractNativeEventFilter
+#endif
 {
   friend class HotkeyWrapper;
 
@@ -207,8 +211,12 @@ protected:
   void unregisterWrapper(HotkeyWrapper *wrapper);
 
 #ifdef Q_OS_WIN32
+# if IS_QT_5
+  virtual bool nativeEventFilter( const QByteArray & eventType, void * message, long * result );
+# else // IS_QT_5
   virtual bool winEventFilter ( MSG * message, long * result );
 #endif
+#endif // Q_OS_WIN32
 
   QList<HotkeyWrapper*> hotkeyWrappers;
 };
diff --git a/hunspell.cc b/hunspell.cc
index 149483ee..34ad9fa6 100644
--- a/hunspell.cc
+++ b/hunspell.cc
@@ -9,17 +9,21 @@
 #include "wstring_qt.hh"
 #include "language.hh"
 #include "langcoder.hh"
+
 #include <QRunnable>
 #include <QThreadPool>
 #include <QSemaphore>
 #include <QRegExp>
 #include <QDir>
 #include <QCoreApplication>
+#include <QFileInfo>
+
 #include <set>
 #include <hunspell/hunspell.hxx>
+
 #include "dprintf.hh"
 #include "fsencoding.hh"
-#include <QFileInfo>
+#include "qt4x5.hh"
 
 namespace HunspellMorpho {
 
@@ -197,7 +201,7 @@ void HunspellArticleRequestRunnable::run()
 
 void HunspellArticleRequest::run()
 {
-  if ( isCancelled )
+  if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
   {
     finish();
     return;
@@ -373,7 +377,7 @@ void HunspellHeadwordsRequestRunnable::run()
 
 void HunspellHeadwordsRequest::run()
 {
-  if ( isCancelled )
+  if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
   {
     finish();
     return;
@@ -597,7 +601,7 @@ void HunspellPrefixMatchRequestRunnable::run()
 
 void HunspellPrefixMatchRequest::run()
 {
-  if ( isCancelled )
+  if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
   {
     finish();
     return;
diff --git a/mainwindow.cc b/mainwindow.cc
index 79619247..12fedc60 100644
--- a/mainwindow.cc
+++ b/mainwindow.cc
@@ -7,7 +7,9 @@
 #include "preferences.hh"
 #include "about.hh"
 #include "mruqmenu.hh"
-#include <limits.h>
+
+#include <QDebug>
+#include <QTextStream>
 #include <QDir>
 #include <QMessageBox>
 #include <QIcon>
@@ -15,16 +17,22 @@
 #include <QToolBar>
 #include <QCloseEvent>
 #include <QDesktopServices>
+#include <QProcess>
+#include <QCryptographicHash>
+#include <QFileDialog>
+#include <QPrinter>
+#include <QPageSetupDialog>
+#include <QPrintPreviewDialog>
+#include <QPrintDialog>
+
+#include <limits.h>
 #include <set>
 #include <map>
 #include "dprintf.hh"
-#include <QDebug>
-#include <QTextStream>
+
 #include "dictinfo.hh"
 #include "fsencoding.hh"
-#include <QProcess>
 #include "historypanewidget.hh"
-#include <QCryptographicHash>
 
 #ifdef Q_OS_MAC
 #include "lionsupport.h"
diff --git a/mdx.cc b/mdx.cc
index a70fd0dc..5a597b6e 100644
--- a/mdx.cc
+++ b/mdx.cc
@@ -35,6 +35,8 @@
 #include <QTextDocument>
 #include <QCryptographicHash>
 
+#include "qt4x5.hh"
+
 namespace Mdx
 {
 
@@ -324,11 +326,11 @@ public:
 
 void MdxDictionary::deferredInit()
 {
-  if ( !deferredInitDone )
+  if ( !Qt4x5::AtomicInt::loadAcquire( deferredInitDone ) )
   {
     Mutex::Lock _( deferredInitMutex );
 
-    if ( deferredInitDone )
+    if ( Qt4x5::AtomicInt::loadAcquire( deferredInitDone ) )
       return;
 
     if ( !deferredInitRunnableStarted )
@@ -349,11 +351,11 @@ string const & MdxDictionary::ensureInitDone()
 
 void MdxDictionary::doDeferredInit()
 {
-  if ( !deferredInitDone )
+  if ( !Qt4x5::AtomicInt::loadAcquire( deferredInitDone ) )
   {
     Mutex::Lock _( deferredInitMutex );
 
-    if ( deferredInitDone )
+    if ( Qt4x5::AtomicInt::loadAcquire( deferredInitDone ) )
       return;
 
     // Do deferred init
@@ -493,7 +495,7 @@ void MdxArticleRequestRunnable::run()
 
 void MdxArticleRequest::run()
 {
-  if ( isCancelled )
+  if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
   {
     finish();
     return;
@@ -525,7 +527,7 @@ void MdxArticleRequest::run()
 
   for ( unsigned x = 0; x < chain.size(); ++x )
   {
-    if ( isCancelled )
+    if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
     {
       finish();
       return;
@@ -671,7 +673,7 @@ void MddResourceRequestRunnable::run()
 
 void MddResourceRequest::run()
 {
-  if ( isCancelled )
+  if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
   {
     finish();
     return;
@@ -690,7 +692,7 @@ void MddResourceRequest::run()
   for ( ;; )
   {
     // Some runnables linger enough that they are cancelled before they start
-    if ( isCancelled )
+    if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
     {
       finish();
       return;
diff --git a/mediawiki.cc b/mediawiki.cc
index c563826f..5dc43a2e 100644
--- a/mediawiki.cc
+++ b/mediawiki.cc
@@ -10,6 +10,7 @@
 #include <list>
 #include "dprintf.hh"
 #include "audiolink.hh"
+#include "qt4x5.hh"
 
 namespace MediaWiki {
 
@@ -112,7 +113,7 @@ MediaWikiWordSearchRequest::MediaWikiWordSearchRequest( wstring const & str,
   DPRINTF( "request begin\n" );
   QUrl reqUrl( url + "/api.php?action=query&list=allpages&aplimit=40&format=xml" );
 
-  reqUrl.addQueryItem( "apfrom", gd::toQString( str ) );
+  Qt4x5::Url::addQueryItem( reqUrl, "apfrom", gd::toQString( str ) );
 
   netReply = mgr.get( QNetworkRequest( reqUrl ) );
 
@@ -252,7 +253,7 @@ void MediaWikiArticleRequest::addQuery( QNetworkAccessManager & mgr,
 
   QUrl reqUrl( url + "/api.php?action=parse&prop=text|revid&format=xml&redirects" );
 
-  reqUrl.addQueryItem( "page", gd::toQString( str ) );
+  Qt4x5::Url::addQueryItem( reqUrl, "page", gd::toQString( str ) );
 
   sptr< QNetworkReply > netReply = mgr.get( QNetworkRequest( reqUrl ) );
   
diff --git a/orderandprops.cc b/orderandprops.cc
index af8f0631..ecc458b6 100644
--- a/orderandprops.cc
+++ b/orderandprops.cc
@@ -7,6 +7,8 @@
 #include "language.hh"
 #include "fsencoding.hh"
 #include <algorithm>
+
+#include <QMenu>
 #include <QPair>
 
 using std::vector;
diff --git a/qt4x5.hh b/qt4x5.hh
new file mode 100644
index 00000000..60b616aa
--- /dev/null
+++ b/qt4x5.hh
@@ -0,0 +1,106 @@
+/* Thin wrappers for retaining compatibility for both Qt4.x and Qt5.x */
+
+#ifndef QT4X5_HH
+#define QT4X5_HH
+
+#if QT_VERSION < QT_VERSION_CHECK(5, 0, 0)
+# define IS_QT_5    0
+#else
+# define IS_QT_5    1
+#endif
+
+#include <QString>
+#include <QAtomicInt>
+#include <QTextDocument>
+
+#include <QUrl>
+#if IS_QT_5
+#include <QUrlQuery>
+#endif
+
+namespace Qt4x5
+{
+
+inline QString escape( QString const & plain )
+{
+#if IS_QT_5
+  return plain.toHtmlEscaped();
+#else
+  return Qt::escape( plain );
+#endif
+
+}
+
+namespace AtomicInt
+{
+
+inline int loadAcquire( QAtomicInt const & ref )
+{
+#if IS_QT_5
+  return ref.loadAcquire();
+#else
+  return ( int )ref;
+#endif
+}
+
+}
+
+namespace Url
+{
+
+inline bool hasQueryItem( QUrl const & url, QString const & key )
+{
+#if IS_QT_5
+  return QUrlQuery( url ).hasQueryItem( key );
+#else
+  return url.hasQueryItem( key );
+#endif
+}
+
+inline QString queryItemValue( QUrl const & url, QString const & item )
+{
+#if IS_QT_5
+  return QUrlQuery( url ).queryItemValue( item );
+#else
+  return url.queryItemValue( item );
+#endif
+}
+
+inline void addQueryItem( QUrl & url, QString const & key, QString const & value )
+{
+#if IS_QT_5
+  QUrlQuery urlQuery( url );
+  urlQuery.addQueryItem( key, value );
+  url.setQuery( urlQuery );
+#else
+  url.addQueryItem( key, value );
+#endif
+}
+
+inline void removeQueryItem( QUrl & url, QString const & key )
+{
+#if IS_QT_5
+  QUrlQuery urlQuery( url );
+  urlQuery.removeQueryItem( key );
+  url.setQuery( urlQuery );
+#else
+  url.removeQueryItem( key );
+#endif
+}
+
+inline void setQueryItems( QUrl & url, QList< QPair< QString, QString > > const & query )
+{
+#if IS_QT_5
+  QUrlQuery urlQuery( url );
+  urlQuery.setQueryItems( query );
+  url.setQuery( urlQuery );
+#else
+  url.setQueryItems( query );
+#endif
+}
+
+}
+
+}
+
+#endif // QT4X5_HH
diff --git a/sdict.cc b/sdict.cc
index 7a158593..022d9435 100644
--- a/sdict.cc
+++ b/sdict.cc
@@ -26,6 +26,7 @@
 #include <QDomDocument>
 
 #include "ufile.hh"
+#include "qt4x5.hh"
 
 namespace Sdict {
 
@@ -406,7 +407,7 @@ void SdictArticleRequestRunnable::run()
 
 void SdictArticleRequest::run()
 {
-  if ( isCancelled )
+  if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
   {
     finish();
     return;
@@ -433,7 +434,7 @@ void SdictArticleRequest::run()
 
   for( unsigned x = 0; x < chain.size(); ++x )
   {
-    if ( isCancelled )
+    if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
     {
       finish();
       return;
diff --git a/sources.cc b/sources.cc
index bf7c5fda..538478f2 100644
--- a/sources.cc
+++ b/sources.cc
@@ -367,7 +367,7 @@ void MediaWikisModel::addNewWiki()
 
 QModelIndex MediaWikisModel::index( int row, int column, QModelIndex const & /*parent*/ ) const
 {
-  return createIndex( row, column, 0 );
+  return createIndex( row, column );
 }
 
 QModelIndex MediaWikisModel::parent( QModelIndex const & /*parent*/ ) const
@@ -524,7 +524,7 @@ void WebSitesModel::addNewSite()
 
 QModelIndex WebSitesModel::index( int row, int column, QModelIndex const & /*parent*/ ) const
 {
-  return createIndex( row, column, 0 );
+  return createIndex( row, column );
 }
 
 QModelIndex WebSitesModel::parent( QModelIndex const & /*parent*/ ) const
@@ -681,7 +681,7 @@ void ProgramsModel::addNewProgram()
 
 QModelIndex ProgramsModel::index( int row, int column, QModelIndex const & /*parent*/ ) const
 {
-  return createIndex( row, column, 0 );
+  return createIndex( row, column );
 }
 
 QModelIndex ProgramsModel::parent( QModelIndex const & /*parent*/ ) const
@@ -870,7 +870,7 @@ void PathsModel::addNewPath( QString const & path )
 
 QModelIndex PathsModel::index( int row, int column, QModelIndex const & /*parent*/ ) const
 {
-  return createIndex( row, column, 0 );
+  return createIndex( row, column );
 }
 
 QModelIndex PathsModel::parent( QModelIndex const & /*parent*/ ) const
@@ -976,7 +976,7 @@ void SoundDirsModel::addNewSoundDir( QString const & path, QString const & name
 
 QModelIndex SoundDirsModel::index( int row, int column, QModelIndex const & /*parent*/ ) const
 {
-  return createIndex( row, column, 0 );
+  return createIndex( row, column );
 }
 
 QModelIndex SoundDirsModel::parent( QModelIndex const & /*parent*/ ) const
@@ -1080,12 +1080,13 @@ HunspellDictsModel::HunspellDictsModel( QWidget * parent,
 void HunspellDictsModel::changePath( QString const & newPath )
 {
   dataFiles = HunspellMorpho::findDataFiles( newPath );
-  reset();
+  beginResetModel();
+  endResetModel();
 }
 
 QModelIndex HunspellDictsModel::index( int row, int column, QModelIndex const & /*parent*/ ) const
 {
-  return createIndex( row, column, 0 );
+  return createIndex( row, column );
 }
 
 QModelIndex HunspellDictsModel::parent( QModelIndex const & /*parent*/ ) const
diff --git a/stardict.cc b/stardict.cc
index eead0451..4d5116e5 100644
--- a/stardict.cc
+++ b/stardict.cc
@@ -36,6 +36,7 @@
 #include <QAtomicInt>
 
 #include "ufile.hh"
+#include "qt4x5.hh"
 
 namespace Stardict {
 
@@ -613,7 +614,7 @@ void StardictHeadwordsRequestRunnable::run()
 
 void StardictHeadwordsRequest::run()
 {
-  if ( isCancelled )
+  if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
   {
     finish();
     return;
@@ -627,7 +628,7 @@ void StardictHeadwordsRequest::run()
 
     for( unsigned x = 0; x < chain.size(); ++x )
     {
-      if ( isCancelled )
+      if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
       {
         finish();
         return;
@@ -733,7 +734,7 @@ void StardictArticleRequestRunnable::run()
 
 void StardictArticleRequest::run()
 {
-  if ( isCancelled )
+  if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
   {
     finish();
     return;
@@ -762,7 +763,7 @@ void StardictArticleRequest::run()
 
     for( unsigned x = 0; x < chain.size(); ++x )
     {
-      if ( isCancelled )
+      if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
       {
         finish();
         return;
@@ -1011,7 +1012,7 @@ void StardictResourceRequestRunnable::run()
 void StardictResourceRequest::run()
 {
   // Some runnables linger enough that they are cancelled before they start
-  if ( isCancelled )
+  if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
   {
     finish();
     return;
diff --git a/texttospeechsource.cc b/texttospeechsource.cc
index edc2199c..21500658 100644
--- a/texttospeechsource.cc
+++ b/texttospeechsource.cc
@@ -180,7 +180,7 @@ void VoiceEnginesModel::addNewVoiceEngine( QString const & id, QString const & n
 
 QModelIndex VoiceEnginesModel::index( int row, int column, QModelIndex const & /*parent*/ ) const
 {
-  return createIndex( row, column, 0 );
+  return createIndex( row, column );
 }
 
 QModelIndex VoiceEnginesModel::parent( QModelIndex const & /*parent*/ ) const
diff --git a/voiceengines.cc b/voiceengines.cc
index e12adb3a..d9b7eaa2 100644
--- a/voiceengines.cc
+++ b/voiceengines.cc
@@ -15,6 +15,8 @@
 #include <QFileInfo>
 #include <QCryptographicHash>
 
+#include "qt4x5.hh"
+
 namespace VoiceEngines
 {
 
@@ -93,7 +95,7 @@ sptr< Dictionary::DataRequest > VoiceEnginesDictionary::getArticle(
   url.setPath( QString::fromUtf8( wordUtf8.c_str() ) );
   QList< QPair<QString, QString> > query;
   query.push_back( QPair<QString, QString>( "engine", QString::fromStdString( getId() ) ) );
-  url.setQueryItems( query );
+  Qt4x5::Url::setQueryItems( url, query );
 
   string encodedUrl = url.toEncoded().data();
   string ref = string( "\"" ) + encodedUrl + "\"";
diff --git a/winlibs/include/hunspell/replist.hxx b/winlibs/include/hunspell/replist.hxx
index 9c37e29b..ea3ed52e 100644
--- a/winlibs/include/hunspell/replist.hxx
+++ b/winlibs/include/hunspell/replist.hxx
@@ -6,6 +6,10 @@
 
 #include "w_char.hxx"
 
+#ifdef near
+# undef near
+#endif
+
 class LIBHUNSPELL_DLL_EXPORTED RepList
 {
 protected:
@@ -24,4 +28,5 @@ public:
     int match(const char * word, int n);
     int conv(const char * word, char * dest);
 };
+
 #endif
diff --git a/winlibs/lib/libhunspell-1.3.a b/winlibs/lib/libhunspell-1.3.a
new file mode 100644
index 00000000..4214b0fb
Binary files /dev/null and b/winlibs/lib/libhunspell-1.3.a differ
diff --git a/xdxf.cc b/xdxf.cc
index a40a56ae..0e8add48 100644
--- a/xdxf.cc
+++ b/xdxf.cc
@@ -36,6 +36,8 @@
 #include <QThreadPool>
 #include <QAtomicInt>
 
+#include "qt4x5.hh"
+
 namespace Xdxf {
 
 using std::map;
@@ -393,7 +395,7 @@ void XdxfArticleRequestRunnable::run()
 
 void XdxfArticleRequest::run()
 {
-  if ( isCancelled )
+  if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
   {
     finish();
     return;
@@ -420,7 +422,7 @@ void XdxfArticleRequest::run()
 
   for( unsigned x = 0; x < chain.size(); ++x )
   {
-    if ( isCancelled )
+    if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
     {
       finish();
       return;
@@ -648,21 +650,21 @@ QString readXhtmlData( QXmlStreamReader & stream )
     {
       QString name = stream.name().toString();
 
-      result += "<" + Qt::escape( name ) + " ";
+      result += "<" + Qt4x5::escape( name ) + " ";
 
       QXmlStreamAttributes attrs = stream.attributes();
 
       for( int x = 0; x < attrs.size(); ++x )
       {
-        result += Qt::escape( attrs[ x ].name().toString() );
-        result += "=\"" + Qt::escape( attrs[ x ].value().toString() ) + "\"";
+        result += Qt4x5::escape( attrs[ x ].name().toString() );
+        result += "=\"" + Qt4x5::escape( attrs[ x ].value().toString() ) + "\"";
       }
 
       result += ">";
 
       result += readXhtmlData( stream );
 
-      result += "</" + Qt::escape( name ) + ">";
+      result += "</" + Qt4x5::escape( name ) + ">";
     }
     else
     if ( stream.isCharacters() || stream.isWhitespace() || stream.isCDATA() )
@@ -862,7 +864,7 @@ void XdxfResourceRequestRunnable::run()
 void XdxfResourceRequest::run()
 {
   // Some runnables linger enough that they are cancelled before they start
-  if ( isCancelled )
+  if ( Qt4x5::AtomicInt::loadAcquire( isCancelled ) )
   {
     finish();
     return;