var pageLoaded = false;
var oldLoadEvent = window.onload;
window.onload = function(){
	if (oldLoadEvent) {
		oldLoadEvent();
	}
	pageLoaded = true;
}
document.body.onclick = function(){
	if(!pageLoaded){
		if(window.event){
			var allow = !CausesPost(window.event.srcElement);
			event.returnValue = allow;
			return allow;
		}else{
			return false;
		}
	}
}
function CausesPost(el){
	if(!el) return false;
	if((el.href && el.href.indexOf('__doPostBack') > -1)
		|| el.tagName == 'INPUT') return true;
	return CausesPost(el.parentElement);
}