Ok, I'll reply in English
(if you wish I can write in German too
)
The ajax request returns an error message:
<div id="logo"></div>
<div id="errorboxbody">
<h2>DateTime::__construct() [<a href='datetime.--construct'>datetime.--construct</a>]: Failed to parse time string (05-10-2011 10:Okt:th) at position 11 (1): Unexpected character</h2>
Did you change the way the date function is formatted? Make sure that you follow the advise given for that setting (just hover over the date setting and you will see that you need to use a different format for joomla 1.5 and 1.7 )
Cheers,
Daniel
P.S. If you cannot fix it, please provide me with both backen + ftp access and I'll have a look.