Element.js

// Upgrade from MooTools Core 1.2 to MooTools Core 1.3
//
// Brings compatibility for Element.set and Element.get with multipe arguments.
// Use at your own risk; if cou can - fix your code and do not use this script.
// -- @cpojer

(function(){

Element.implement({
	
	// from 1.2
	set: function(prop, value){
		switch (typeOf(prop)){
			case 'object':
				for (var p in prop) this.set(p, prop[p]);
				break;
			case 'string':
				var property = Element.Properties[prop];
				(property && property.set) ? property.set.apply(this, Array.slice(arguments, 1)) : this.setProperty(prop, value);
		}
		return this;
	},

	get: function(prop){
		var property = Element.Properties[prop];
		return (property && property.get) ? property.get.apply(this, Array.slice(arguments, 1)) : this.getProperty(prop);
	}
	
});

var props = Element.Properties;

var wrap = function(prop){
	if (!props[prop]) return wrap;
	var getter = props[prop].get;
	props[prop].get = function(options){
		if (options) this.set(prop, options);
		return getter.call(this);
	};
	return wrap;
};

wrap('tween')('morph')('load')('send');

})(Element.Properties);