diff --git a/lib/kcommondecoration.cpp b/lib/kcommondecoration.cpp
index 6625407ee3..dca6eaaa04 100644
--- a/lib/kcommondecoration.cpp
+++ b/lib/kcommondecoration.cpp
@@ -796,7 +796,7 @@ bool KCommonDecoration::isToolWindow() const
     return ((type==NET::Toolbar)||(type==NET::Utility)||(type==NET::Menu));
 }
 
-QRect KCommonDecoration::titleRect()
+QRect KCommonDecoration::titleRect() const
 {
     int r_x, r_y, r_x2, r_y2;
     widget()->rect().coords(&r_x, &r_y, &r_x2, &r_y2);
@@ -809,7 +809,7 @@ QRect KCommonDecoration::titleRect()
     const int ttlHeight = layoutMetric(LM_TitleHeight);
     const int titleEdgeBottomBottom = r_y+titleEdgeTop+ttlHeight+titleEdgeBottom-1;
     return QRect(r_x+titleEdgeLeft+buttonsLeftWidth()+titleBorderLeft, r_y+titleEdgeTop,
-              r_x2-titleEdgeRight-buttonsRightWidth()-(r_x+titleEdgeLeft+buttonsLeftWidth()+titleBorderLeft),
+              r_x2-titleEdgeRight-buttonsRightWidth()-titleBorderRight-(r_x+titleEdgeLeft+buttonsLeftWidth()+titleBorderLeft),
               titleEdgeBottomBottom-(r_y+titleEdgeTop) );
 }
 
diff --git a/lib/kcommondecoration.h b/lib/kcommondecoration.h
index 47bfd3a215..67ace366c9 100644
--- a/lib/kcommondecoration.h
+++ b/lib/kcommondecoration.h
@@ -216,7 +216,7 @@ class KWIN_EXPORT KCommonDecoration : public KDecoration
          * Convenience method.
          * @returns the title rect.
          */
-         QRect titleRect();
+         QRect titleRect() const;
 
     public:
         /**