[Mediawiki-l] Empty Page after mySQL-Upgrade (4.x => 5.x)

[Jan]

Hello!

I'm running two MW-Installations von my webspace: 1.6 and 1.9-SVN, 
standard-configured.

Last night my Webhoster has upgraded the MySQL Version from 4.1.x to "MySQL - 
5.0.30-Debian_1~bpo.1". php was updated from 5.? to 5.2.0-7~bpo.1.

Now both wikis only display absolutely empty pages in firefox (0 Byte HTML are 
returned).
In IE7 i get an error-message: "Die Webseite kann nicht angezeigt werden." 
(translated: "The website cant be displayed").

I tried: "php update.php", delete localsettings.php and re-run webinstaller 
(standard-localsettings, only DB-conntection configurated)
... without success.

Other php-Skript with mySQL are still running (e.g. Gallery).

URL is:
http://mwbeta.fokkograf.de

Any tipps?

Best regards,
Jan