diff --git a/setup.py b/setup.py
index 2e0d0d6..52e5616 100644
--- a/setup.py
+++ b/setup.py
@@ -214,6 +214,7 @@ class build_ext(sipdistutils.build_ext):
         # /usr/bin/rcc -name ads ../../Qt-Advanced-Docking-System/src/ads.qrc -o release/qrc_ads.cpp
         
         cppsources = [source for source in ext.sources if source.endswith(".cpp")]
+        headersources = ['src/DockAreaTitleBar_p.h']
 
         dir_util.mkpath(self.build_temp, dry_run=self.dry_run)
 
@@ -247,6 +248,30 @@ class build_ext(sipdistutils.build_ext):
                 if os.path.getsize(out_file) > 0:
                     ext.sources.append(out_file)
 
+        # Run moc on all orphan header files.
+        for source in headersources:
+            # *.cpp -> *.moc
+            moc_file = os.path.basename(source).replace(".h", ".moc")
+            out_file = os.path.join(self.build_temp, moc_file)
+
+            if newer(source, out_file) or self.force:
+                spawn.spawn(get_moc_args(out_file, source),
+                            dry_run=self.dry_run)
+
+            header = source
+            if os.path.exists(header):
+                # *.h -> moc_*.cpp
+                moc_file = "moc_" + os.path.basename(header).replace(
+                    ".h", ".cpp")
+                out_file = os.path.join(self.build_temp, moc_file)
+
+                if newer(header, out_file) or self.force:
+                    spawn.spawn(get_moc_args(out_file, header),
+                                dry_run=self.dry_run)
+
+                if os.path.getsize(out_file) > 0:
+                    ext.sources.append(out_file)
+
         # Add the temp build directory to include path, for compiler to find
         # the created .moc files
         ext.include_dirs += [self._sip_output_dir()]
diff --git a/sip/DockAreaTitleBar_p.sip b/sip/DockAreaTitleBar_p.sip
new file mode 100644
index 0000000..0ae3339
--- /dev/null
+++ b/sip/DockAreaTitleBar_p.sip
@@ -0,0 +1,37 @@
+%Import QtWidgets/QtWidgetsmod.sip
+
+%If (Qt_5_0_0 -)
+
+namespace ads
+{
+
+class CTitleBarButton : QToolButton
+{
+    %TypeHeaderCode
+    #include <DockAreaTitleBar_p.h>
+    %End
+
+protected:
+    bool event(QEvent *ev);
+
+public:
+    CTitleBarButton(bool visible = true, QWidget* parent /TransferThis/ = Q_NULLPTR );
+    virtual void setVisible(bool visible);
+};
+
+
+class CSpacerWidget : QWidget
+{
+    %TypeHeaderCode
+    #include <DockAreaTitleBar_p.h>
+    %End
+
+public:
+	CSpacerWidget(QWidget* Parent /TransferThis/ = 0 );
+	virtual QSize sizeHint() const;
+	virtual QSize minimumSizeHint() const;
+};
+
+};
+
+%End
diff --git a/sip/DockAreaWidget.sip b/sip/DockAreaWidget.sip
index e105f69..dbe1c7e 100644
--- a/sip/DockAreaWidget.sip
+++ b/sip/DockAreaWidget.sip
@@ -4,7 +4,7 @@
 
 namespace ads
 {
-    
+
 class CDockAreaWidget : QFrame
 {
 
@@ -32,6 +32,7 @@ public:
 	virtual ~CDockAreaWidget();
 	ads::CDockManager* dockManager() const;
 	ads::CDockContainerWidget* dockContainer() const;
+	virtual QSize minimumSizeHint() const;
 	QRect titleBarGeometry() const;
 	QRect contentAreaGeometry() const;
 	int dockWidgetsCount() const;
diff --git a/sip/DockManager.sip b/sip/DockManager.sip
index 7a6d5e7..dcb9cbf 100644
--- a/sip/DockManager.sip
+++ b/sip/DockManager.sip
@@ -194,8 +194,8 @@ public:
 	const QList<ads::CDockContainerWidget*> dockContainers() const;
 	const QList<ads::CFloatingDockContainer*> floatingWidgets() const;
 	unsigned int zOrderIndex() const;
-	QByteArray saveState(int version = 1) const;
-	bool restoreState(const QByteArray &state, int version = 1);
+	QByteArray saveState(int version = 0) const;
+	bool restoreState(const QByteArray &state, int version = 0);
 	void addPerspective(const QString& UniquePrespectiveName);
 	void removePerspective(const QString& Name);
 	void removePerspectives(const QStringList& Names);
diff --git a/sip/FloatingDockContainer.sip b/sip/FloatingDockContainer.sip
index 38c4ab6..4e80db5 100644
--- a/sip/FloatingDockContainer.sip
+++ b/sip/FloatingDockContainer.sip
@@ -27,6 +27,7 @@ public:
 
 	virtual void moveFloating() = 0;
 	virtual void finishDragging() = 0;
+	virtual ~IFloatingWidget();
 };
 
 
@@ -56,6 +57,10 @@ protected:
 	virtual void closeEvent(QCloseEvent *event);
 	virtual void hideEvent(QHideEvent *event);
 	virtual void showEvent(QShowEvent *event);
+	%If (WS_WIN)
+	virtual bool nativeEvent(const QByteArray &eventType, void *message, long *result);
+	%End
+
 
 public:
 	CFloatingDockContainer(ads::CDockManager* DockManager /TransferThis/);
diff --git a/sip/FloatingDragPreview.sip b/sip/FloatingDragPreview.sip
index 659af35..9a76e0b 100644
--- a/sip/FloatingDragPreview.sip
+++ b/sip/FloatingDragPreview.sip
@@ -13,7 +13,6 @@ class CFloatingDragPreview : QWidget, ads::IFloatingWidget
     %End
 
 protected:
-	virtual void moveEvent(QMoveEvent *event);
 	virtual void paintEvent(QPaintEvent *e);
 	CFloatingDragPreview(QWidget* Content /TransferThis/, QWidget* parent /TransferThis/);
 
diff --git a/sip/ads.sip b/sip/ads.sip
index fe92502..8da5d64 100644
--- a/sip/ads.sip
+++ b/sip/ads.sip
@@ -5,6 +5,7 @@
 %Include ads_globals.sip
 %Include DockWidget.sip
 %Include DockAreaTabBar.sip
+%Include DockAreaTitleBar_p.sip
 %Include DockAreaTitleBar.sip
 %Include DockAreaWidget.sip
 %Include DockComponentsFactory.sip
diff --git a/sip/ads_globals.sip b/sip/ads_globals.sip
index ea78457..ead6b0e 100644
--- a/sip/ads_globals.sip
+++ b/sip/ads_globals.sip
@@ -8,13 +8,6 @@ namespace ads
     #include <ads_globals.h>
     %End
 
-    enum eStateFileVersion
-    {
-        InitialVersion,
-        Version1,
-        CurrentVersion
-    };
-
     enum DockWidgetArea
     {
         NoDockWidgetArea,