MobileWeb: Using apply() to run an event handler in a specific scope

On iOS, I can use the following function to set scope for an event handler:

var oxi = {};
oxi.bind = function(scope, fn) {
        return function() {
            fn.apply(scope, arguments);
        };
};
 
// Setting event handler in "this" scope:
 
Ti.App.addEventListener('CUSTOM:MyCustomEvent',oxi.bind(this,myDefinedFunction));
 
// Removing event handler 
 
Ti.App.removeEventListener('CUSTOM:MyCustomEvent',oxi.bind(this,myDefinedFunction));

However, on MobileWeb the event handler is not removed - so it seems the bind-method on the addEventListener and removeEventListener aren't refering to the same function anymore.