function popup(URL) {
	var pupHeight;
	var pupWidth;
			
	if(is.p == 'win' && is.b == 'ns') { pupHeight=425;pupWidth=350; }
	else if (is.p == 'win' && is.b == 'ie') { pupHeight=305;pupWidth=340; }
	else if (is.p == 'mac' && is.b == 'ie') { pupHeight=305;pupWidth=300; }
	else if (is.p == 'mac' && is.b == 'ns') { pupHeight=325;pupWidth=350; }
	else if (is.p == 'bsd' && is.b == 'ns') { pupHeight=400;pupWidth=300; }
	else { pupHeight=400;pupWidth=400; }
			
	var popwin;
	popwin = window.open(URL, 'popup', 'height=' + pupHeight + ',width=' + pupWidth + ',screenx=160,screeny=160,location=no,resizable=yes,scrollbars=yes,status=no,toolbar=no');
	popwin.focus();
	popwin.moveTo(160,160);
}