function open_window( page_name, window_name, width, height) {
	
    args = "width=" + width + "," 
    + "height=" + height + "," 
    + "location=0," 
    + "menubar=1,"
    + "resizable=1,"
    + "scrollbars=1,"
    + "status=1," 
    + "titlebar=0,"
    + "toolbar=0,"
    + "hotkeys=0,"

    window.open( page_name,window_name,args );
}