import german translation stuck/hang

whenever i try to update the german translations - my incoming_ and outgoing_translations tables are empty - the browser shows "Finding files" and hangs forever. The system is running stable with all other features. Only "Update languages" does not work. In the logs i get messages like this after every attempt:

error: Database_Exception [ 44 ]: #2006: MySQL server has gone away [ SELECT *

Gallery version (not just "2"): 3.0.2
PHP version (e.g. 5.1.6): 5.3.8
PHPInfo Link (see FAQ):
Webserver (e.g. Apache 1.3.33): 1.3.42
Database (e.g. MySql 5.0.32): 5.5.16
Activated toolkits (e.g. NetPbm, GD):
Operating system (e.g. Linux): CentOS 5.7
Browser (e.g. Firefox 2.0): Firefox 5