Vanilla Object extension

extend.js

Object.extend = function() {
	var args = Array.prototype.slice.call(arguments);
	var destination = args.shift();
	var i = 0;
 
	while(i < args.length) {
		var source = args[i];
 
		for(prop in source) {
			if(Object.prototype.hasOwnProperty.call(source, prop)) {
				if(typeof source[prop] === "object") {
					destination[prop] = destination[prop] || {};
					arguments.callee(destination[prop], source[prop]);
				} else {
					destination[prop] = source[prop];
				}
			}
		}
 
		i++;
	}
 
	return destination;
};