diff --git a/src/servers/app/BitmapDrawingEngine.cpp b/src/servers/app/BitmapDrawingEngine.cpp
index ce7f1d24fa..6927842b50 100644
--- a/src/servers/app/BitmapDrawingEngine.cpp
+++ b/src/servers/app/BitmapDrawingEngine.cpp
@@ -18,6 +18,23 @@ BitmapDrawingEngine::~BitmapDrawingEngine()
 }
 
 
+bool
+BitmapDrawingEngine::IsParallelAccessLocked() const
+{
+	// We don't share the HWInterface instance that the Painter is
+	// attached to, so we never need to be locked.
+	return true;
+}
+
+
+bool
+BitmapDrawingEngine::IsExclusiveAccessLocked() const
+{
+	// See IsParallelAccessLocked().
+	return true;
+}
+
+
 status_t
 BitmapDrawingEngine::SetSize(int32 newWidth, int32 newHeight)
 {
@@ -63,7 +80,7 @@ BitmapDrawingEngine::SetSize(int32 newWidth, int32 newHeight)
 }
 
 
-UtilityBitmap *
+UtilityBitmap*
 BitmapDrawingEngine::ExportToBitmap(int32 width, int32 height,
 	color_space space)
 {
diff --git a/src/servers/app/BitmapDrawingEngine.h b/src/servers/app/BitmapDrawingEngine.h
index b8d98f4ae6..f81fa3597b 100644
--- a/src/servers/app/BitmapDrawingEngine.h
+++ b/src/servers/app/BitmapDrawingEngine.h
@@ -12,13 +12,18 @@ public:
 								BitmapDrawingEngine();
 virtual							~BitmapDrawingEngine();
 
+#if DEBUG
+	virtual	bool				IsParallelAccessLocked() const;
+#endif
+	virtual	bool				IsExclusiveAccessLocked() const;
+
 			status_t			SetSize(int32 newWidth, int32 newHeight);
-			UtilityBitmap *		ExportToBitmap(int32 width, int32 height,
+			UtilityBitmap*		ExportToBitmap(int32 width, int32 height,
 									color_space space);
 
 private:
-			BitmapHWInterface *	fHWInterface;
-			UtilityBitmap *		fBitmap;
+			BitmapHWInterface*	fHWInterface;
+			UtilityBitmap*		fBitmap;
 			BRegion				fClipping;
 };
 
diff --git a/src/servers/app/Desktop.cpp b/src/servers/app/Desktop.cpp
index 5aeeec6f5c..85c83002c3 100644
--- a/src/servers/app/Desktop.cpp
+++ b/src/servers/app/Desktop.cpp
@@ -1197,7 +1197,12 @@ Desktop::MoveWindowBy(Window* window, float x, float y, int32 workspace)
 	// moved into the dirty region (for now)
 	newDirtyRegion.Include(&window->VisibleRegion());
 
-	GetDrawingEngine()->CopyRegion(&copyRegion, (int32)x, (int32)y);
+	// NOTE: Having all windows locked should prevent any
+	// problems with locking the drawing engine here.
+	if (GetDrawingEngine()->LockParallelAccess()) {
+		GetDrawingEngine()->CopyRegion(&copyRegion, (int32)x, (int32)y);
+		GetDrawingEngine()->UnlockParallelAccess();
+	}
 
 	// in the dirty region, exclude the parts that we
 	// could move by blitting
diff --git a/src/servers/app/Window.cpp b/src/servers/app/Window.cpp
index b3a87aa76d..16dbd31a03 100644
--- a/src/servers/app/Window.cpp
+++ b/src/servers/app/Window.cpp
@@ -468,22 +468,28 @@ Window::CopyContents(BRegion* region, int32 xOffset, int32 yOffset)
 				if (allDirtyRegions != NULL)
 					copyRegion->Exclude(allDirtyRegions);
 
-				fDrawingEngine->CopyRegion(copyRegion, xOffset, yOffset);
+				if (fDrawingEngine->LockParallelAccess()) {
+					fDrawingEngine->CopyRegion(copyRegion, xOffset, yOffset);
+					fDrawingEngine->UnlockParallelAccess();
 
-				// Prevent those parts from being added to the dirty region...
-				newDirty->Exclude(copyRegion);
+					// Prevent those parts from being added to the dirty region...
+					newDirty->Exclude(copyRegion);
 
-				// The parts that could be copied are not dirty (at the
-				// target location!)
-				copyRegion->OffsetBy(xOffset, yOffset);
-				// ... and even exclude them from the pending dirty region!
-				if (fPendingUpdateSession->IsUsed())
-					fPendingUpdateSession->DirtyRegion().Exclude(copyRegion);
+					// The parts that could be copied are not dirty (at the
+					// target location!)
+					copyRegion->OffsetBy(xOffset, yOffset);
+					// ... and even exclude them from the pending dirty region!
+					if (fPendingUpdateSession->IsUsed())
+						fPendingUpdateSession->DirtyRegion().Exclude(copyRegion);
+				}
 
 				fRegionPool.Recycle(copyRegion);
 			} else {
 				// Fallback, should never be here.
-				fDrawingEngine->CopyRegion(region, xOffset, yOffset);
+				if (fDrawingEngine->LockParallelAccess()) {
+					fDrawingEngine->CopyRegion(region, xOffset, yOffset);
+					fDrawingEngine->UnlockParallelAccess();
+				}
 			}
 
 			if (allDirtyRegions != NULL)
diff --git a/src/servers/app/drawing/DrawingEngine.cpp b/src/servers/app/drawing/DrawingEngine.cpp
index 28974f2baa..3627b98ec5 100644
--- a/src/servers/app/drawing/DrawingEngine.cpp
+++ b/src/servers/app/drawing/DrawingEngine.cpp
@@ -458,7 +458,7 @@ void
 DrawingEngine::CopyRegion(/*const*/ BRegion* region, int32 xOffset,
 	int32 yOffset)
 {
-	ASSERT_EXCLUSIVE_LOCKED();
+	ASSERT_PARALLEL_LOCKED();
 
 	BRect frame = region->Frame();
 	frame = frame | frame.OffsetByCopy(xOffset, yOffset);
diff --git a/src/servers/app/drawing/DrawingEngine.h b/src/servers/app/drawing/DrawingEngine.h
index ef8a811507..4dd95cf2bb 100644
--- a/src/servers/app/drawing/DrawingEngine.h
+++ b/src/servers/app/drawing/DrawingEngine.h
@@ -51,12 +51,12 @@ public:
 	// locking
 			bool			LockParallelAccess();
 #if DEBUG
-			bool			IsParallelAccessLocked() const;
+	virtual	bool			IsParallelAccessLocked() const;
 #endif
 			void			UnlockParallelAccess();
 
 			bool			LockExclusiveAccess();
-			bool			IsExclusiveAccessLocked();
+	virtual	bool			IsExclusiveAccessLocked();
 			void			UnlockExclusiveAccess();
 
 	// for screen shots