diff --git a/ui/effects.core.js b/ui/effects.core.js
index 2cc7542f2..e41d71441 100644
--- a/ui/effects.core.js
+++ b/ui/effects.core.js
@@ -222,8 +222,18 @@ $.fn.extend({
 	},
 
 	_toggleClass: $.fn.toggleClass,
-	toggleClass: function(classNames,speed,easing,callback) {
-		return ( (typeof speed !== "boolean") && speed ) ? $.effects.animateClass.apply(this, [{ toggle: classNames },speed,easing,callback]) : this._toggleClass(classNames, speed);
+	toggleClass: function(classNames, force, speed, easing, callback) {
+		if ( typeof force == "boolean" || force === undefined ) {
+			if ( !speed ) {
+				// without speed parameter;
+				return this._toggleClass(classNames, force);
+			} else {
+				return $.effects.animateClass.apply(this, [(force?{add:classNames}:{remove:classNames}),speed,easing,callback]);
+			}
+		} else {
+			// without switch parameter;
+			return $.effects.animateClass.apply(this, [{ toggle: classNames },force,speed,easing]);
+		}
 	},
 
 	switchClass: function(remove,add,speed,easing,callback) {