function __textBoxPostBack(e, id) { 
	var keynum; 
	if(window.event) { 
		keynum = e.keyCode; 
	} else if(e.which) { 
		keynum = e.which; 
	} 
	if(keynum == 13) { 
		__doPostBack(id, ''); 
		return false;
	} 
}