Problems with gettext.php

Hello,

since a few days I got without Warning frequently error messages on loading my page. (it doesn´t occur every time, if it occurs, the page finally loads normal after reloading it 1-2 times)

Without warning means it started without any changes, updates or ne plugins.

I´m a bit confused, because the error did never occur before.

This is my Site:
http://blog.indonesia-portal.de

The error message is this one:

Warning: unpack() [function.unpack]: Type V: not enough input, need 4, have 0 in /www/htdocs/w0081622/de/blog/wp-includes/gettext.php on line 84

It should have something to do with the german language file (for the admin menu and perhaps some plugins), because, when I delete the german language file, it seems, that the error occurs less frequently.

PHP version: 5.0.37
MySql: 5.0
Linux-Based Server
(don´t know anything more specific)

The error occurs also very often, when im working in the admin menu, it occurs less when im just going through articles on my site (after it was finally loaded without the error).

It also seems, that im not the only one, who suffers from this error. Different people told about it and they were hosted by different providers.

*edit: Just one more thing: People, using WP 2.31 also got this problem. So, it seems, that it has nothing to do with the version.

Thanks for any help,
Marc