function popUp(pageId, w, h) {
	var y = (screen.availHeight - h) / 2;
	var x = (screen.availWidth  - w) / 2;
	
	var myWin = window.open('/popup.php?page='+pageId, 'popup', 'width='+w+', height='+h+', left='+x+', top='+y+', scrollbars=yes');
	myWin.focus();
}

function orderAllowed ( amount ) {	
	if ( amount == "" || amount == undefined || amount < 6 ) {
		alert("De minimale bestelhoeveelheid is 6 flessen."); 
	} else {
		window.location = "/shop/winkelwagen_gegevens/";
	}
}