diff --git a/effects.cpp b/effects.cpp
index 11104adfe8..ad4695dd7f 100644
--- a/effects.cpp
+++ b/effects.cpp
@@ -25,6 +25,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "group.h"
 #include "scene_xrender.h"
 #include "scene_opengl.h"
+#include "unmanaged.h"
 #include "workspace.h"
 #include "kwinglutils.h"
 
@@ -429,6 +430,15 @@ int EffectsHandlerImpl::displayHeight() const
     return KWin::displayWidth();
     }
 
+EffectWindow* EffectsHandlerImpl::findWindow( WId id ) const
+    {
+    if( Client* w = Workspace::self()->findClient( WindowMatchPredicate( id )))
+        return w->effectWindow();
+    if( Unmanaged* w = Workspace::self()->findUnmanaged( WindowMatchPredicate( id )))
+        return w->effectWindow();
+    return NULL;
+    }
+
 EffectWindowList EffectsHandlerImpl::stackingOrder() const
     {
     ClientList list = Workspace::self()->stackingOrder();
diff --git a/effects.h b/effects.h
index 2a10f5b5a1..fecded05d7 100644
--- a/effects.h
+++ b/effects.h
@@ -63,6 +63,7 @@ class EffectsHandlerImpl : public EffectsHandler
         virtual QPoint cursorPos() const;
         virtual bool grabKeyboard( Effect* effect );
         virtual void ungrabKeyboard();
+        virtual EffectWindow* findWindow( WId id ) const;
         virtual EffectWindowList stackingOrder() const;
         virtual void setElevatedWindow( EffectWindow* w, bool set );
 
diff --git a/lib/kwineffects.h b/lib/kwineffects.h
index 471ff3978e..8bb82ef31f 100644
--- a/lib/kwineffects.h
+++ b/lib/kwineffects.h
@@ -40,7 +40,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 #define KWIN_EFFECT_API_MAKE_VERSION( major, minor ) (( major ) << 8 | ( minor )) 
 #define KWIN_EFFECT_API_VERSION_MAJOR 0
-#define KWIN_EFFECT_API_VERSION_MINOR 4
+#define KWIN_EFFECT_API_VERSION_MINOR 5
 #define KWIN_EFFECT_API_VERSION KWIN_EFFECT_API_MAKE_VERSION( \
     KWIN_EFFECT_API_VERSION_MAJOR, KWIN_EFFECT_API_VERSION_MINOR )
 
@@ -381,6 +381,7 @@ class KWIN_EXPORT EffectsHandler
         virtual int desktopUp( int desktop, bool wrap ) const = 0;
         virtual int desktopDown( int desktop, bool wrap ) const = 0;
 
+        virtual EffectWindow* findWindow( WId id ) const = 0;
         virtual EffectWindowList stackingOrder() const = 0;
         // window will be temporarily painted as if being at the top of the stack
         virtual void setElevatedWindow( EffectWindow* w, bool set ) = 0;