function ajax(ajax_cont_id,ajax_url){

loader="/im/load.gif";
loader="<table width=100% height=100% border=0><tr><td valign=center align=middle><img src='"+loader+"'></td></tr></table>";

eval("tmp=document.getElementById('"+ajax_cont_id+"')");
//if(!tmp)alert("Layer "+ajax_cont_id+" existiert nicht!");
//alert(ajax_url);

if(tmp)
{
eval("document.getElementById('"+ajax_cont_id+"').display='block';");
//eval("document.getElementById('"+ajax_cont_id+"').innerHTML = loader;");

//erstellen des requests
var req = null;

try{
req = new XMLHttpRequest();
}
catch (ms){
try{
req = new ActiveXObject("Msxml2.XMLHTTP");
}
catch (nonms){
try{
req = new ActiveXObject("Microsoft.XMLHTTP");
}
catch (failed){
req = null;
}
}
}

if (req == null)
alert("Error creating request object!");

//anfrage erstellen (GET, url ist localhost,
//request ist asynchron
req.open("GET", ajax_url, true);
//req.open("GET", 'http://www.erfrischte-eschringer.de', true);

//Beim abschliessen des request wird diese Funktion ausgeführt
req.onreadystatechange = function(){
switch(req.readyState) {
case 4:
if(req.status!=200) {
//alert("Fehler:"+req.status);
}else{
//alert(req.responseText);
//schreibe die antwort in den div container mit der id content
eval("document.getElementById('"+ajax_cont_id+"').innerHTML = req.responseText;");
//top.document.getElementById(ajax_cont_id).innerHTML = req.responseText;
}
break;

default:
return false;
break;
}
};

req.setRequestHeader("Content-Type",
"application/x-www-form-urlencoded");
req.send(null);
}

}