var ajaxObj = new Ajax();

function addOverlay(uri) {
	var overlay = document.createElement("div");
	var overlayBody = document.createElement("div");
	var overlayBackground = document.createElement("div");
	var close = document.createElement("div");

	overlayBackground.id = "overlay-background";
	overlayBackground.className = "overlay-background";
	overlayBackground.style.position = "absolute";
	overlayBackground.style.width = "100%";
	overlayBackground.style.height = getContainerHeight() + "px";
	overlayBackground.style.top = "0px";
	overlayBackground.style.left = "0px";
	
	overlayBody.innerHTML = ajaxObj.getResponse(uri);
	overlayBody.id = "overlay-body";
	overlayBody.className = "overlay-body";

	close.id = "overlay-close";
	close.className = "overlay-close";
	close.setAttribute("onclick", "document.body.removeChild(document.getElementById('overlay')); return false");
	close.style.position = "absolute";
	close.style.cursor = "pointer";
	
	overlay.id = "overlay";
	overlay.className = "overlay";
	
	overlay.appendChild(overlayBackground);
	overlay.appendChild(overlayBody);
	overlay.appendChild(close);
	
	document.body.appendChild(overlay);
}

function getContainerHeight() {
	if (document.layers) 
		return document.getElementById('container').style.clip.bottom;
		
	return document.getElementById('container').offsetHeight;
}