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, lpx , tpx , opt_position){
if (document.getElementById){
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"
 
subobj.style.left=lpx+"px"
subobj.style.top=tpx+"px"
 
document.getElementById('maincontent').style.display="none"
 

return false
}
else
return true
}
 
function overlayclose(subobj){
 document.getElementById(subobj).style.display="none"
 document.getElementById('maincontent').style.display="block"
}