var xhrcount = 0;
function mypxhr(callback,tpath,tvars,as,dtype){
var handle = callback;
var url = tpath;	
var varparam = tvars;
var asmethod = as;
var tpe = dtype;
var myAjax = new Ajax.Request(
	url,
	{
    	_method: asmethod,
		method: asmethod,
   		parameters: varparam,
   		onComplete: function(response) {
		if(tpe=='xml'){
		myObj =response;
		}else{
		myObj =response.responseText.evalJSON();
		}
		(handle!=false)?handle(myObj):null;
		myAjax = false;
	},
 	    onFailure: function(t) {
			++xhrcount;
			if(xhrcount<4){
			mypxhr(url,varparam);
			}else{
			alert('Our service is temporily unavailable. Please try again later.');
			}
   	}
	});
}