function addListener(obj,event_,callback){
	if(obj.addEventListener){
		obj.addEventListener(event_,callback,false);
	}else{
		obj.attachEvent("on"+event_,callback);
	}
}

/******************************************************************************************************************/
// Externe JS-Dateien laden (nach allen anderen in der HTML im Head definierten)
function inc(fileName){
	var script = document.createElement('script');
	script.type = 'text/javascript';
	script.src = fileName;
	(document.getElementsByTagName('HEAD')[0] || document.body).appendChild(script);
	return script;
}