function openPopup(target, url,width,height, scrollbars)
{
	
	if(width > 0 && height > 0)
	{
		var centered;
		x = (screen.availWidth - width) / 2;
		y = (screen.availHeight - height) / 2;
		centered =',width=' + width + ',height=' + height + ',left=' + x + ',top=' + y + ',scrollbars='+scrollbars+',resizable=yes,status=yes';
	}else
	{
		centered = 'scrollbars='+scrollbars+',resizable=yes,status=yes';
	}	
	var popup = window.open(url, target, centered);
  	if (!popup.opener) popup.opener = self;
	popup.focus();
}