function check(message)	{
	var answer = confirm(message);
	return answer;
}	

function popup(seite, w, h)	{
	var l = (screen.width-w)/2; 
	var o = (screen.height-h)/2; 
	window.open(seite, 'Bildanzeige', 'scrollbars=no, resizable=yes, width='+ w +', height='+ h +',left='+ l +',screenX='+ l +',top='+ o +',screenY='+ o);
}