//----------------------------------------------------- add event listerners
function addEvent(obj, evType, fn){ 
	if (obj.addEventListener){ 
		obj.addEventListener(evType, fn, false); 
		return true; 
	} else if (obj.attachEvent){ 
		var r = obj.attachEvent("on"+evType, fn); 
		return r; 
	} else { 
		return false; 
	} 
}
//------------------------------------------------------------ pop up window
function survey(){
	if(!window.popwin){
		popwin = window.open('survey.php','survey','width=350,height=350');
	}
}
//------------------------------------------------------------- attach event
addEvent(document, 'click', survey);