diff --git a/cmake/Modules/winconf.cmake b/cmake/Modules/winconf.cmake
index 7dc7907bd..6976657f8 100644
--- a/cmake/Modules/winconf.cmake
+++ b/cmake/Modules/winconf.cmake
@@ -24,6 +24,7 @@ add_definitions(-DUNICODE
     -D_WIN32_IE=0x0501
     -D_CRT_SECURE_NO_DEPRECATE
     -D_SCL_SECURE_NO_DEPRECATE
+    -DNOMINMAX
 )
 # and boost
 set(Boost_USE_STATIC_LIBS  True)
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 3137057ca..fc08356ce 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -40,11 +40,8 @@ include_directories(${CMAKE_CURRENT_SOURCE_DIR})
 
 # defines
 add_definitions(-DQT_NO_CAST_TO_ASCII)
-# Fast concatenation (Qt >= 4.6)
-add_definitions(-DQT_USE_FAST_CONCATENATION -DQT_USE_FAST_OPERATOR_PLUS)
-if (WIN32)
-    add_definitions(-DNOMINMAX)
-endif (WIN32)
+# Efficient construction for QString & QByteArray (Qt >= 4.8)
+add_definitions(-DQT_USE_QSTRINGBUILDER)
 
 if (NOT GUI)
     add_definitions(-DDISABLE_GUI -DDISABLE_COUNTRIES_RESOLUTION)
diff --git a/src/base/net/smtp.cpp b/src/base/net/smtp.cpp
index fcc35b2e3..5a9f203cb 100644
--- a/src/base/net/smtp.cpp
+++ b/src/base/net/smtp.cpp
@@ -194,7 +194,7 @@ void Smtp::readyRead()
                 ehlo();
             }
             else {
-                logError("Connection failed, unrecognized reply: " + line);
+                logError(QLatin1String("Connection failed, unrecognized reply: ") + line);
                 m_state = Close;
             }
             break;
@@ -231,7 +231,7 @@ void Smtp::readyRead()
             }
             else {
                 // Authentication failed!
-                logError("Authentication failed, msg: " + line);
+                logError(QLatin1String("Authentication failed, msg: ") + line);
                 m_state = Close;
             }
             break;
@@ -242,7 +242,7 @@ void Smtp::readyRead()
                 m_state = Data;
             }
             else {
-                logError("<mail from> was rejected by server, msg: " + line);
+                logError(QLatin1String("<mail from> was rejected by server, msg: ") + line);
                 m_state = Close;
             }
             break;
@@ -253,7 +253,7 @@ void Smtp::readyRead()
                 m_state = Body;
             }
             else {
-                logError("<Rcpt to> was rejected by server, msg: " + line);
+                logError(QLatin1String("<Rcpt to> was rejected by server, msg: ") + line);
                 m_state = Close;
             }
             break;
@@ -264,7 +264,7 @@ void Smtp::readyRead()
                 m_state = Quit;
             }
             else {
-                logError("<data> was rejected by server, msg: " + line);
+                logError(QLatin1String("<data> was rejected by server, msg: ") + line);
                 m_state = Close;
             }
             break;
@@ -276,7 +276,7 @@ void Smtp::readyRead()
                 m_state = Close;
             }
             else {
-                logError("Message was rejected by the server, error: " + line);
+                logError(QLatin1String("Message was rejected by the server, error: ") + line);
                 m_state = Close;
             }
             break;
diff --git a/src/gui/about.qrc b/src/gui/about.qrc
index da886b454..e6133f7ca 100644
--- a/src/gui/about.qrc
+++ b/src/gui/about.qrc
@@ -1,7 +1,7 @@
-<!DOCTYPE RCC><RCC version="1.0">
-<qresource>
-  <file>gpl.html</file>
-  <file>thanks.html</file>
-  <file>translators.html</file>
-</qresource>
+<RCC>
+    <qresource prefix="/">
+        <file>gpl.html</file>
+        <file>thanks.html</file>
+        <file>translators.html</file>
+    </qresource>
 </RCC>
diff --git a/src/gui/properties/trackersadditiondlg.cpp b/src/gui/properties/trackersadditiondlg.cpp
index cf98eea63..5a63f9fd7 100644
--- a/src/gui/properties/trackersadditiondlg.cpp
+++ b/src/gui/properties/trackersadditiondlg.cpp
@@ -105,7 +105,7 @@ void TrackersAdditionDlg::parseUTorrentList(const QString &, const QString &path
         m_ui->trackers_list->insertPlainText("\n");
     int nb = 0;
     while (!list_file.atEnd()) {
-        const QByteArray line = list_file.readLine().trimmed();
+        const QString line = list_file.readLine().trimmed();
         if (line.isEmpty()) continue;
         BitTorrent::TrackerEntry newTracker(line);
         if (!existingTrackers.contains(newTracker)) {
diff --git a/src/icons.qrc b/src/icons.qrc
index b3247798f..257b9813a 100644
--- a/src/icons.qrc
+++ b/src/icons.qrc
@@ -1,14 +1,6 @@
 <RCC>
     <qresource prefix="/">
-        <file>icons/qbittorrent.png</file>
         <file>icons/3-state-checkbox.gif</file>
-        <file>icons/L.gif</file>
-        <file>icons/loading.png</file>
-        <file>icons/slow.png</file>
-        <file>icons/slow_off.png</file>
-        <file>icons/sphere.png</file>
-        <file>icons/sphere2.png</file>
-        <file>icons/url.png</file>
         <file>icons/flags/ad.png</file>
         <file>icons/flags/ae.png</file>
         <file>icons/flags/af.png</file>
@@ -250,9 +242,13 @@
         <file>icons/flags/za.png</file>
         <file>icons/flags/zm.png</file>
         <file>icons/flags/zw.png</file>
+        <file>icons/L.gif</file>
+        <file>icons/loading.png</file>
+        <file>icons/qbittorrent.png</file>
         <file>icons/qbt-theme/application-exit.png</file>
         <file>icons/qbt-theme/application-rss+xml.png</file>
         <file>icons/qbt-theme/application-x-mswinurl.png</file>
+        <file>icons/qbt-theme/checked.png</file>
         <file>icons/qbt-theme/configure.png</file>
         <file>icons/qbt-theme/dialog-cancel.png</file>
         <file>icons/qbt-theme/dialog-information.png</file>
@@ -280,7 +276,9 @@
         <file>icons/qbt-theme/folder-remote.png</file>
         <file>icons/qbt-theme/gear.png</file>
         <file>icons/qbt-theme/gear32.png</file>
+        <file>icons/qbt-theme/go-bottom.png</file>
         <file>icons/qbt-theme/go-down.png</file>
+        <file>icons/qbt-theme/go-top.png</file>
         <file>icons/qbt-theme/go-up.png</file>
         <file>icons/qbt-theme/help-about.png</file>
         <file>icons/qbt-theme/help-contents.png</file>
@@ -299,14 +297,17 @@
         <file>icons/qbt-theme/network-server.png</file>
         <file>icons/qbt-theme/network-wired.png</file>
         <file>icons/qbt-theme/object-locked.png</file>
+        <file>icons/qbt-theme/office-chart-line.png</file>
         <file>icons/qbt-theme/preferences-desktop.png</file>
         <file>icons/qbt-theme/preferences-other.png</file>
         <file>icons/qbt-theme/preferences-system-network.png</file>
         <file>icons/qbt-theme/preferences-web-browser-cookies.png</file>
+        <file>icons/qbt-theme/rss-config.png</file>
         <file>icons/qbt-theme/security-high.png</file>
         <file>icons/qbt-theme/security-low.png</file>
         <file>icons/qbt-theme/services.png</file>
         <file>icons/qbt-theme/speedometer.png</file>
+        <file>icons/qbt-theme/system-log-out.png</file>
         <file>icons/qbt-theme/tab-close.png</file>
         <file>icons/qbt-theme/task-attention.png</file>
         <file>icons/qbt-theme/task-complete.png</file>
@@ -332,6 +333,7 @@
         <file>icons/skin/bg-panel-header.gif</file>
         <file>icons/skin/checking.png</file>
         <file>icons/skin/collapse-expand.gif</file>
+        <file>icons/skin/completed.png</file>
         <file>icons/skin/connected.png</file>
         <file>icons/skin/disconnected.png</file>
         <file>icons/skin/dock-tabs.gif</file>
@@ -350,13 +352,14 @@
         <file>icons/skin/logo2.gif</file>
         <file>icons/skin/mascot.png</file>
         <file>icons/skin/paused.png</file>
+        <file>icons/skin/qbittorrent-tray-dark.svg</file>
+        <file>icons/skin/qbittorrent-tray-light.svg</file>
         <file>icons/skin/qbittorrent16.png</file>
         <file>icons/skin/qbittorrent22.png</file>
         <file>icons/skin/qbittorrent32.png</file>
-        <file>icons/skin/qbittorrent-tray-dark.svg</file>
-        <file>icons/skin/qbittorrent-tray-light.svg</file>
         <file>icons/skin/queued.png</file>
         <file>icons/skin/ratio.png</file>
+        <file>icons/skin/resumed.png</file>
         <file>icons/skin/seeding.png</file>
         <file>icons/skin/slider-area.gif</file>
         <file>icons/skin/spacer.gif</file>
@@ -368,14 +371,11 @@
         <file>icons/skin/tabs.gif</file>
         <file>icons/skin/toolbox-divider.gif</file>
         <file>icons/skin/toolbox-divider2.gif</file>
-        <file>icons/skin/resumed.png</file>
         <file>icons/skin/uploading.png</file>
-        <file>icons/skin/completed.png</file>
-        <file>icons/qbt-theme/system-log-out.png</file>
-        <file>icons/qbt-theme/go-bottom.png</file>
-        <file>icons/qbt-theme/go-top.png</file>
-        <file>icons/qbt-theme/checked.png</file>
-        <file>icons/qbt-theme/office-chart-line.png</file>
-        <file>icons/qbt-theme/rss-config.png</file>
+        <file>icons/slow.png</file>
+        <file>icons/slow_off.png</file>
+        <file>icons/sphere.png</file>
+        <file>icons/sphere2.png</file>
+        <file>icons/url.png</file>
     </qresource>
 </RCC>
diff --git a/src/lang.qrc b/src/lang.qrc
index 60002a62a..611602950 100644
--- a/src/lang.qrc
+++ b/src/lang.qrc
@@ -1,54 +1,54 @@
-<!DOCTYPE RCC><RCC version="1.0">
-<qresource>
-  <file>lang/qbittorrent_ar.qm</file>
-  <file>lang/qbittorrent_be.qm</file>
-  <file>lang/qbittorrent_bg.qm</file>
-  <file>lang/qbittorrent_ca.qm</file>
-  <file>lang/qbittorrent_cs.qm</file>
-  <file>lang/qbittorrent_da.qm</file>
-  <file>lang/qbittorrent_de.qm</file>
-  <file>lang/qbittorrent_el.qm</file>
-  <file>lang/qbittorrent_en.qm</file>
-  <file>lang/qbittorrent_en_AU.qm</file>
-  <file>lang/qbittorrent_en_GB.qm</file>
-  <file>lang/qbittorrent_es.qm</file>
-  <file>lang/qbittorrent_eo.qm</file>
-  <file>lang/qbittorrent_eu.qm</file>
-  <file>lang/qbittorrent_fi.qm</file>
-  <file>lang/qbittorrent_fr.qm</file>
-  <file>lang/qbittorrent_gl.qm</file>
-  <file>lang/qbittorrent_he.qm</file>
-  <file>lang/qbittorrent_hi_IN.qm</file>
-  <file>lang/qbittorrent_hr.qm</file>
-  <file>lang/qbittorrent_hu.qm</file>
-  <file>lang/qbittorrent_hy.qm</file>
-  <file>lang/qbittorrent_id.qm</file>
-  <file>lang/qbittorrent_is.qm</file>
-  <file>lang/qbittorrent_it.qm</file>
-  <file>lang/qbittorrent_ja.qm</file>
-  <file>lang/qbittorrent_ka.qm</file>
-  <file>lang/qbittorrent_ko.qm</file>
-  <file>lang/qbittorrent_lv_LV.qm</file>
-  <file>lang/qbittorrent_lt.qm</file>
-  <file>lang/qbittorrent_ms_MY.qm</file>
-  <file>lang/qbittorrent_nb.qm</file>
-  <file>lang/qbittorrent_nl.qm</file>
-  <file>lang/qbittorrent_oc.qm</file>
-  <file>lang/qbittorrent_pl.qm</file>
-  <file>lang/qbittorrent_pt_PT.qm</file>
-  <file>lang/qbittorrent_pt_BR.qm</file>
-  <file>lang/qbittorrent_ro.qm</file>
-  <file>lang/qbittorrent_ru.qm</file>
-  <file>lang/qbittorrent_sk.qm</file>
-  <file>lang/qbittorrent_sl.qm</file>
-  <file>lang/qbittorrent_sr.qm</file>
-  <file>lang/qbittorrent_sv.qm</file>
-  <file>lang/qbittorrent_tr.qm</file>
-  <file>lang/qbittorrent_uk.qm</file>
-  <file>lang/qbittorrent_uz@Latn.qm</file>
-  <file>lang/qbittorrent_vi.qm</file>
-  <file>lang/qbittorrent_zh.qm</file>
-  <file>lang/qbittorrent_zh_TW.qm</file>
-  <file>lang/qbittorrent_zh_HK.qm</file>
-</qresource>
+<RCC>
+    <qresource prefix="/">
+        <file>lang/qbittorrent_ar.qm</file>
+        <file>lang/qbittorrent_be.qm</file>
+        <file>lang/qbittorrent_bg.qm</file>
+        <file>lang/qbittorrent_ca.qm</file>
+        <file>lang/qbittorrent_cs.qm</file>
+        <file>lang/qbittorrent_da.qm</file>
+        <file>lang/qbittorrent_de.qm</file>
+        <file>lang/qbittorrent_el.qm</file>
+        <file>lang/qbittorrent_en.qm</file>
+        <file>lang/qbittorrent_en_AU.qm</file>
+        <file>lang/qbittorrent_en_GB.qm</file>
+        <file>lang/qbittorrent_eo.qm</file>
+        <file>lang/qbittorrent_es.qm</file>
+        <file>lang/qbittorrent_eu.qm</file>
+        <file>lang/qbittorrent_fi.qm</file>
+        <file>lang/qbittorrent_fr.qm</file>
+        <file>lang/qbittorrent_gl.qm</file>
+        <file>lang/qbittorrent_he.qm</file>
+        <file>lang/qbittorrent_hi_IN.qm</file>
+        <file>lang/qbittorrent_hr.qm</file>
+        <file>lang/qbittorrent_hu.qm</file>
+        <file>lang/qbittorrent_hy.qm</file>
+        <file>lang/qbittorrent_id.qm</file>
+        <file>lang/qbittorrent_is.qm</file>
+        <file>lang/qbittorrent_it.qm</file>
+        <file>lang/qbittorrent_ja.qm</file>
+        <file>lang/qbittorrent_ka.qm</file>
+        <file>lang/qbittorrent_ko.qm</file>
+        <file>lang/qbittorrent_lt.qm</file>
+        <file>lang/qbittorrent_lv_LV.qm</file>
+        <file>lang/qbittorrent_ms_MY.qm</file>
+        <file>lang/qbittorrent_nb.qm</file>
+        <file>lang/qbittorrent_nl.qm</file>
+        <file>lang/qbittorrent_oc.qm</file>
+        <file>lang/qbittorrent_pl.qm</file>
+        <file>lang/qbittorrent_pt_BR.qm</file>
+        <file>lang/qbittorrent_pt_PT.qm</file>
+        <file>lang/qbittorrent_ro.qm</file>
+        <file>lang/qbittorrent_ru.qm</file>
+        <file>lang/qbittorrent_sk.qm</file>
+        <file>lang/qbittorrent_sl.qm</file>
+        <file>lang/qbittorrent_sr.qm</file>
+        <file>lang/qbittorrent_sv.qm</file>
+        <file>lang/qbittorrent_tr.qm</file>
+        <file>lang/qbittorrent_uk.qm</file>
+        <file>lang/qbittorrent_uz@Latn.qm</file>
+        <file>lang/qbittorrent_vi.qm</file>
+        <file>lang/qbittorrent_zh.qm</file>
+        <file>lang/qbittorrent_zh_HK.qm</file>
+        <file>lang/qbittorrent_zh_TW.qm</file>
+    </qresource>
 </RCC>
diff --git a/src/searchengine.qrc b/src/searchengine.qrc
index 35dea1b8a..0a91aac8c 100644
--- a/src/searchengine.qrc
+++ b/src/searchengine.qrc
@@ -1,16 +1,16 @@
 <RCC>
     <qresource prefix="/">
-        <file>searchengine/nova/fix_encoding.py</file>
-        <file>searchengine/nova/helpers.py</file>
-        <file>searchengine/nova/nova2.py</file>
-        <file>searchengine/nova/novaprinter.py</file>
-        <file>searchengine/nova/socks.py</file>
         <file>searchengine/nova3/helpers.py</file>
         <file>searchengine/nova3/nova2.py</file>
+        <file>searchengine/nova3/nova2dl.py</file>
         <file>searchengine/nova3/novaprinter.py</file>
         <file>searchengine/nova3/sgmllib3.py</file>
         <file>searchengine/nova3/socks.py</file>
+        <file>searchengine/nova/fix_encoding.py</file>
+        <file>searchengine/nova/helpers.py</file>
+        <file>searchengine/nova/nova2.py</file>
         <file>searchengine/nova/nova2dl.py</file>
-        <file>searchengine/nova3/nova2dl.py</file>
+        <file>searchengine/nova/novaprinter.py</file>
+        <file>searchengine/nova/socks.py</file>
     </qresource>
 </RCC>
diff --git a/src/src.pro b/src/src.pro
index c3b2c0ec9..081e6e825 100644
--- a/src/src.pro
+++ b/src/src.pro
@@ -6,26 +6,22 @@ CONFIG += qt thread silent
 CONFIG += c++11
 DEFINES += BOOST_NO_CXX11_RVALUE_REFERENCES
 
-# Windows specific configuration
+# Platform specific configuration
 win32: include(../winconf.pri)
-
-# Mac specific configuration
 macx: include(../macxconf.pri)
-
-# Unix specific configuration
 unix:!macx: include(../unixconf.pri)
-
-# eCS(OS/2) specific configuration
 os2: include(../os2conf.pri)
 
+QT += network xml
+
 nogui {
+    TARGET = qbittorrent-nox
     QT -= gui
     DEFINES += DISABLE_GUI
-    TARGET = qbittorrent-nox
 } else {
-    macx: QT += macextras
-    macx: LIBS += -lobjc
+    TARGET = qbittorrent
     QT += xml concurrent svg widgets
+
     CONFIG(static) {
         DEFINES += QBT_STATIC_QT
         QTPLUGIN += qico
@@ -33,16 +29,19 @@ nogui {
     win32 {
         QT += winextras
     }
-    TARGET = qbittorrent
+    macx {
+        QT += macextras
+        LIBS += -lobjc
+    }
+}
+nowebui {
+    DEFINES += DISABLE_WEBUI
 }
-nowebui: DEFINES += DISABLE_WEBUI
 strace_win {
     DEFINES += STACKTRACE_WIN
     DEFINES += STACKTRACE_WIN_PROJECT_PATH=$$PWD
     DEFINES += STACKTRACE_WIN_MAKEFILE_PATH=$$OUT_PWD
 }
-QT += network xml
-
 
 CONFIG(debug, debug|release): message(Project is built in DEBUG mode.)
 CONFIG(release, debug|release): message(Project is built in RELEASE mode.)
@@ -57,10 +56,8 @@ CONFIG(release, debug|release) {
 include(../version.pri)
 
 DEFINES += QT_NO_CAST_TO_ASCII
-# Fast concatenation (Qt >= 4.6)
-DEFINES += QT_USE_FAST_CONCATENATION QT_USE_FAST_OPERATOR_PLUS
-
-win32: DEFINES += NOMINMAX
+# Efficient construction for QString & QByteArray (Qt >= 4.8)
+DEFINES += QT_USE_QSTRINGBUILDER
 
 INCLUDEPATH += $$PWD
 
diff --git a/src/webui/webui.qrc b/src/webui/webui.qrc
index 7af7dafef..c1e481195 100644
--- a/src/webui/webui.qrc
+++ b/src/webui/webui.qrc
@@ -2,12 +2,24 @@
     <qresource prefix="/">
         <file>www/private/index.html</file>
         <file>www/private/login.html</file>
+        <file>www/public/about.html</file>
+        <file>www/public/addtrackers.html</file>
+        <file>www/public/confirmdeletion.html</file>
         <file>www/public/css/Core.css</file>
         <file>www/public/css/dynamicTable.css</file>
         <file>www/public/css/Layout.css</file>
         <file>www/public/css/style.css</file>
         <file>www/public/css/Tabs.css</file>
         <file>www/public/css/Window.css</file>
+        <file>www/public/download.html</file>
+        <file>www/public/downloadlimit.html</file>
+        <file>www/public/filters.html</file>
+        <file>www/public/newcategory.html</file>
+        <file>www/public/preferences.html</file>
+        <file>www/public/preferences_content.html</file>
+        <file>www/public/properties.html</file>
+        <file>www/public/properties_content.html</file>
+        <file>www/public/rename.html</file>
         <file>www/public/scripts/client.js</file>
         <file>www/public/scripts/clipboard.min.js</file>
         <file>www/public/scripts/contextmenu.js</file>
@@ -15,33 +27,21 @@
         <file>www/public/scripts/dynamicTable.js</file>
         <file>www/public/scripts/excanvas-compressed.js</file>
         <file>www/public/scripts/misc.js</file>
-        <file>www/public/scripts/mocha.js</file>
         <file>www/public/scripts/mocha-init.js</file>
         <file>www/public/scripts/mocha-yc.js</file>
+        <file>www/public/scripts/mocha.js</file>
         <file>www/public/scripts/mootools-1.2-core-yc.js</file>
         <file>www/public/scripts/mootools-1.2-more.js</file>
         <file>www/public/scripts/parametrics.js</file>
         <file>www/public/scripts/progressbar.js</file>
-        <file>www/public/about.html</file>
-        <file>www/public/addtrackers.html</file>
-        <file>www/public/confirmdeletion.html</file>
-        <file>www/public/download.html</file>
-        <file>www/public/downloadlimit.html</file>
-        <file>www/public/filters.html</file>
-        <file>www/public/preferences.html</file>
-        <file>www/public/preferences_content.html</file>
-        <file>www/public/properties.html</file>
-        <file>www/public/properties_content.html</file>
+        <file>www/public/scripts/prop-files.js</file>
         <file>www/public/scripts/prop-general.js</file>
         <file>www/public/scripts/prop-trackers.js</file>
         <file>www/public/scripts/prop-webseeds.js</file>
-        <file>www/public/scripts/prop-files.js</file>
+        <file>www/public/setlocation.html</file>
         <file>www/public/statistics.html</file>
         <file>www/public/transferlist.html</file>
         <file>www/public/upload.html</file>
         <file>www/public/uploadlimit.html</file>
-        <file>www/public/newcategory.html</file>
-        <file>www/public/setlocation.html</file>
-        <file>www/public/rename.html</file>
     </qresource>
 </RCC>
diff --git a/winconf.pri b/winconf.pri
index ca36e0a92..dcec302ca 100644
--- a/winconf.pri
+++ b/winconf.pri
@@ -49,6 +49,7 @@ DEFINES += _CRT_SECURE_NO_DEPRECATE
 DEFINES += _SCL_SECURE_NO_DEPRECATE
 DEFINES += __USE_W32_SOCKETS
 DEFINES += _FILE_OFFSET_BITS=64
+DEFINES += NOMINMAX
 
 CONFIG(debug, debug|release) {
   DEFINES += TORRENT_DEBUG