function getposOffset(overlay, offsettype){
var entireOffset=(offsettype=="left")? overlay.offsetLeft : overlay.offsetTop;
var parentElement=overlay.offsetParent;
while (parentElement!=null){
entireOffset=(offsettype=="left")? entireOffset+parentElement.offsetLeft : entireOffset+parentElement.offsetTop;
parentElement=parentElement.offsetParent;
}
return entireOffset;
}

function overlay(curobj, subobjectstr, opt_position){
if (document.getElementById){
var subObject=document.getElementById(subobjectstr)
subObject.style.display=(subObject.style.display!="block")? "block" : "none"
var xPosition=getposOffset(curobj, "left")+((typeof opt_position!="undefined" && opt_position.indexOf("right")!=-1)? -(subObject.offsetWidth-curobj.offsetWidth) : 0) 
var yPosition=getposOffset(curobj, "top")+((typeof opt_position!="undefined" && opt_position.indexOf("bottom")!=-1)? curobj.offsetHeight : 0)
subObject.style.left=xPosition+"px"
subObject.style.top=yPosition+"px"
return false
}
else
return true
}

function overlayclose(subObject){
document.getElementById(subObject).style.display="none"
}