var NewWindow;

function openNewWindow(URL,width,height) {
	if((NewWindow == null ) || NewWindow.closed ) {
 		Parameters = new String("left="+(window.screen.availWidth/2 - width/2)+",top="+(window.screen.availHeight/2 - height/2) + ",height="+height+",width="+width+", status=1,location=0,directories=0,toolbar=no,menubar=0,scrollbars=no,resizable=yes");
		NewWindow = window.open(URL,'pop',Parameters);
	}
	else {
		NewWindow.location = URL;
		NewWindow.focus();
	}
}