Error when saving a topic

Hello,

I think I found a bug in the software. Maybe there's someone who knows the effect.

I'm testing the software using one special user which is member of a group.

The group got special rights for some forums (exactly: nearly ALL rights).

The user himself has no additional rights.

But when I post a topic logged in as this user I have problems while saving the topic.

There's a very strange effect, I think it is a bug in an sql string:

When saving the topic the software overwrites the group membership of the user in the table tblAuthor.

I think it must be a bug in an sql string. Probably there is an update query which writes in the false table column.

But which query is it and how could I find it?

Thanks in advance for any help.

Thomas