function centerwinreg(HTMLPage) {
    	w = 480; h = 460; var Xwin = 0; var Ywin = 0;
        if (parseInt(navigator.appVersion) >= 4) {
            Xwin = (screen.availWidth - w)*.5;
            Ywin = (screen.availHeight - h)*.5;
        	}
		displayWindow = window.open(HTMLPage,'displayWindow','toolbar=0,location=0,directories=0,status=0,menubar=0,scrollbars=0,resizable=0,copyhistory=0,width='+w+',height='+h+',left='+Xwin+',top='+Ywin)
   		if(displayWindow.opener == null) displayWindow.opener = self;
		}