In any of the above mentioned browsers, the inheritance doesn't seem to work using the this.sup() method as the caller's name is an empty string(the caller being anonymous function).

A possible solution:

instead of this code: try { var caller = this.sup.caller.name; this.supers[caller].apply(this, arguments); } catch(noSuper) { return false; }

this code may work in all of the browsers var caller = this.sup.caller.name; try { this.supers[caller].apply(this, arguments); } catch(noSuper) { if(caller === ''){ for (var i in this.supers) { if (i && this.supers[i] === this.sup.caller) { this.supers[i].apply(this, arguments); } } } return false; }

This method may give you a the same output despite of the browser.(sorry, didn't have tried this code).