diff --git a/src/mousetracker.js b/src/mousetracker.js
index 60500660..eb1fb94f 100644
--- a/src/mousetracker.js
+++ b/src/mousetracker.js
@@ -192,7 +192,7 @@
             mouseupcaptured:       function ( event ) { onMouseUpCaptured( _this, event ); },
             mousemove:             function ( event ) { onMouseMove( _this, event ); },
             mousemovecaptured:     function ( event ) { onMouseMoveCaptured( _this, event ); },
-            
+
             mouseoutdocument:      function ( event ) { onMouseUp( _this, event ); },
 
             touchenter:            function ( event ) { onTouchEnter( _this, event ); },
@@ -1053,7 +1053,7 @@
             }
 
             // handle mouse out of document area
-            $.addEvent(document, "mouseout",  delegate['mouseoutdocument']);
+            $.addEvent(document, "mouseout",  delegate.mouseoutdocument);
 
             delegate.tracking = true;
         }
@@ -1081,7 +1081,7 @@
             }
 
             // handle mouse out of document area
-            $.removeEvent(document, "mouseout",  delegate['mouseoutdocument']);
+            $.removeEvent(document, "mouseout",  delegate.mouseoutdocument);
 
             delegate.tracking = false;
         }