function popup( href, name, h, l ) {
	var hauteur = Math.round( ( screen.availHeight - h ) / 2 );
	var largeur = Math.round( ( screen.availWidth - l ) / 2 );
	var popup = window.open( href, name, 'toolbar=0,location=0,directories=0,status=0, scrollbars=1,resizable=1,menubar=0,top='+hauteur+',left='+largeur+',width='+l+',height='+h);
	popup.focus();
	return false;	
}

function popupArticle( Obj ) {
	return popup( Obj.href, 'article', 640, 680 );
}
function popupNews( Obj ) {
	return popup( Obj.href, 'news', 640, 580 );
}
function popupNewsletter( Obj ) {
	return popup( Obj.href, 'newsletter', 410, 340 );
}