var proto = new this(null); 
var proto = new this($empty); 
	extend: function(properties){		var proto = new this(null);		for (var property in properties){			var pp = proto[property];			proto[property] = Class.Merge(pp, properties[property]);		}		return new Class(proto);	},
9299	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/9299/06922312396df156a34eea7232801f69ce9461b7/Class.js/buggy/Class/Class.js