[TYPO3-ttnews] tt_news fails to save Category in news items

[Edern Appéré]

Hi,

I'm sending this email to get some help since we are experiencing a 
weird problem with tt_news right now.

First, some background information about our Typo3 installation : Debian 
server runing Apache 2 with PHP 5.2 ; Typo3 4.2.6, tt_news 2.5.2.

There are actually at least seven websites powered by this Typo3 
installation. None of them encountered any problem until last week. We 
noticed that some MySQL errors appeared in the Typo3 backend but not for 
all users, for contributors only (we saw them since we enabled 
"sqldebug" option in Install-tool) and right now it has become 
impossible for a contributor to attribute a category to a news item. The 
category seems to be stored in the database but when editing the news 
item the category doesn't appear in the "relations" tab.

Have you ever heard of this kind of issue ?

We searched in every possible way (remove Tt_news, clear tables, and so 
on) but to no result so far.
Any help would be really appreciated !

Best regards,

Edern