diff -urNw aquavcl01/vcl/aqua/inc/salframe.h myaquavcl01/vcl/aqua/inc/salframe.h
--- aquavcl01/vcl/aqua/inc/salframe.h	2006-04-27 15:47:01.000000000 -0500
+++ myaquavcl01/vcl/aqua/inc/salframe.h	2006-07-26 15:22:33.000000000 -0500
@@ -77,7 +77,10 @@
 	int                     mnMinHeight;            // min. client height in pixeln
 	int                     mnMaxWidth;             // max. client width in pixeln
 	int                     mnMaxHeight;            // max. client height in pixeln
+	Rect                    maFullScreenRect;       // old window size when in FullScreen
+	WindowAttributes        maFullScreenAttr;       // old window attributes when in FullScreen
 	BOOL			mbGraphics; 		// is Graphics used?  
+	BOOL                    mbFullScreen;           // is Window in FullScreen?
 	AquaSalInstance*        mpSalInstance;
 
 public:
diff -urNw aquavcl01/vcl/aqua/source/window/salframe.cxx myaquavcl01/vcl/aqua/source/window/salframe.cxx
--- aquavcl01/vcl/aqua/source/window/salframe.cxx	2006-07-19 05:22:11.000000000 -0500
+++ myaquavcl01/vcl/aqua/source/window/salframe.cxx	2006-07-28 06:31:56.000000000 -0500
@@ -69,6 +69,27 @@
 	return 0;
 }
 
+static void ImplSalCalcFullScreenSize( const AquaSalFrame* pFrame, Rect* pSize )
+{	
+	/** FIXME ** 
+	 * Implement multiple displays here. That's why a pointer
+	 * to frame is passed. But pointer not currently used.
+	 **/
+	CGDirectDisplayID mainDisplayID = CGMainDisplayID();
+	printf("Display ID %d\n", mainDisplayID);
+	
+	CGRect rect;
+	rect = CGDisplayBounds( mainDisplayID );
+	printf( "Screen resolution: %fx%f\n", rect.size.width, rect.size.height );
+	
+	// Stores current resolution in pSize.
+	// Rect made out of ints -> cast required -> CGRect made out of floats.
+	pSize->top = 0;
+	pSize->left = 0;
+	pSize->bottom = static_cast<int>(rect.size.height);
+	pSize->right = static_cast<int>(rect.size.width);
+}
+
 // =======================================================================
 
 AquaSalFrame::AquaSalFrame() :
@@ -345,6 +366,29 @@
 void AquaSalFrame::ShowFullScreen( BOOL bFullScreen )
 {
     fprintf(stderr, ">*>_> %s\n",__func__);
+	
+	if( mbFullScreen == bFullScreen )
+		return;
+	
+	mbFullScreen = bFullScreen;
+	AquaSalFrame* pFrame = this;
+	if( bFullScreen )
+	{
+		Rect newBounds;
+		ImplSalCalcFullScreenSize( pFrame, &newBounds ); // Get new bounds
+		GetWindowAttributes( mrWindow, &maFullScreenAttr ); // Save attributes
+		ChangeWindowAttributes( mrWindow, kWindowNoAttributes, maFullScreenAttr );
+		GetWindowBounds( mrWindow, kWindowContentRgn, &maFullScreenRect );
+		SetWindowBounds( mrWindow, kWindowContentRgn, &newBounds );
+		SetSystemUIMode( kUIModeAllHidden, kUIOptionAutoShowMenuBar );
+		// -> Shows menubar when we move the mouse over it.
+	}
+	else
+	{
+		SetWindowBounds( mrWindow, kWindowContentRgn, &maFullScreenRect );
+		ChangeWindowAttributes( mrWindow, maFullScreenAttr, kWindowNoAttributes );
+		SetSystemUIMode( kUIModeNormal, nil );
+	}
 }
 
 // -----------------------------------------------------------------------