function getposOffset(overlay, offsettype){
	var totaloffset = (offsettype == "left") ? overlay.offsetLeft : overlay.offsetTop;
	var parentEl = overlay.offsetParent;
	while (parentEl != null){
		totaloffset = (offsettype == "left") ? totaloffset + parentEl.offsetLeft : totaloffset + parentEl.offsetTop;
		parentEl = parentEl.offsetParent;
	}
	return totaloffset;
}
function overlay(curobj, subobjstr, opt_position){
	var subobj = document.getElementById(subobjstr);
	subobj.style.display = (subobj.style.display != "block") ? "block" : "none";
	var xpos = getposOffset(curobj, "left") + ((typeof opt_position != "undefined" && opt_position.indexOf("right") != -1) ? - (subobj.offsetWidth - curobj.offsetWidth) : 0);
	var ypos = getposOffset(curobj, "top") + ((typeof opt_position != "undefined" && opt_position.indexOf("bottom") != -1) ? curobj.offsetHeight : 0);
	subobj.style.left = xpos + "px";
	subobj.style.top = ypos + "px";
	return false;
}
function overlayclose(subobj){
	$(subobj).style.display = 'none';
}