function gf_PopUpWindow(URL, WindowName, WindowWidth, WindowHeight) {
	PosX = Math.round(screen.availWidth / 2) - (WindowWidth / 2) 
	PosY = Math.round(screen.availHeight / 2) - (WindowHeight / 2) - 20
	
	popupwin = window.open(URL,WindowName,"scrollbars=yes,resizable=yes,directories=no,menubar=no,screenx=" + PosX + ",screeny=" + PosY + ",left=" + PosX + ",top=" + PosY + ",status=no,titlebar=yes,toolbar=no,height=" + WindowHeight + ",width=" + WindowWidth )
    popupwin.focus();
}