function openCenteredWindow(url, windowName, width, height, otherParams)
{

	var winX = Math.round((screen.availWidth/2) - (width/2));
	var winY = Math.round((screen.availHeight/2) - (height/2));

	var params = "width=" + width + ",innerWidth=" + width + ",height=" + height +
			",innerHeight=" + height + ",left=" + winX + ",top=" + winY;

	if(otherParams)
		params += "," + otherParams;

	return window.open(url, windowName, params);

}