First try to update the java plugin. If this doesn't work you have to look in your settings if you find something there that advices the browser to ignore appleats.

Thanks, but that didn't help me. I don't find anything, that makes my Internet Explorer ignoring the applets. Maybe someone is able to answer in german, too.

Are you sure it's just IE? Have you tried other browsers? In German (sorry if it's bad. Spreche ich Deutsch nicht die Beste.): Bist du sicher, es ist nur Internet Explorer? Haben Sie anderen Browsern versucht?