diff --git a/src/buttongroup.js b/src/buttongroup.js
index 550a2ac1..da0f658a 100644
--- a/src/buttongroup.js
+++ b/src/buttongroup.js
@@ -119,7 +119,7 @@ $.ButtonGroup.prototype = {
      * @name OpenSeadragon.ButtonGroup.prototype.emulateEnter
      */
     emulateEnter: function() {
-        this.tracker.enterHandler();
+        this.tracker.enterHandler( this.tracker, {} );
     },
 
     /**
@@ -129,7 +129,7 @@ $.ButtonGroup.prototype = {
      * @name OpenSeadragon.ButtonGroup.prototype.emulateExit
      */
     emulateExit: function() {
-        this.tracker.exitHandler();
+        this.tracker.exitHandler( this.tracker, {} );
     }
 };
 
diff --git a/src/viewer.js b/src/viewer.js
index 7c374daa..88df1d81 100644
--- a/src/viewer.js
+++ b/src/viewer.js
@@ -730,7 +730,7 @@ $.extend( $.Viewer.prototype, $.EventHandler.prototype, $.ControlDock.prototype,
             THIS[ this.hash ].fullPage = true;
 
             // mouse will be inside container now
-            $.delegate( this, onContainerEnter )();
+            $.delegate( this, onContainerEnter )( null, {} );
 
 
         } else {
@@ -789,7 +789,7 @@ $.extend( $.Viewer.prototype, $.EventHandler.prototype, $.ControlDock.prototype,
             THIS[ this.hash ].fullPage = false;
 
             // mouse will likely be outside now
-            $.delegate( this, onContainerExit )();
+            $.delegate( this, onContainerExit )( null, {} );
 
 
         }