diff -Nauwr source/Irrlicht/CIrrDeviceWin32.cpp source/Irrlicht/CIrrDeviceWin32.cpp
--- source/Irrlicht/CIrrDeviceWin32.cpp	2005-08-24 17:58:34.000000000 +0200
+++ source/Irrlicht/CIrrDeviceWin32.cpp	2005-09-21 20:39:38.000000000 +0200
@@ -600,7 +600,7 @@
 //! returns if window is active. if not, nothing need to be drawn
 bool CIrrDeviceWin32::isWindowActive()
 {
-	bool ret = (GetActiveWindow() == HWnd);
+	bool ret = (GetActiveWindow() == GetAncestor(HWnd,GA_ROOT));
 	_IRR_IMPLEMENT_MANAGED_MARSHALLING_BUGFIX;	
 	return ret;
 }