> I have a multithreaded program running atop IBPP on Firebird 2.1.1.

Do you play by the MT-safe rules ? The easiest is to not share same attachment
by different theads or to manually syncronize access to it. Also you should serialize
calls of attach\detach database.

And upgrade up to 2.1.3, it is safe.

> the program and firebird is running on the same machine, using a socket.

So, use local protocol (XNET) for more speed.

> does anybody know how to solve this? it's quite critical.

It depends. And we should know more info from you...

> i consider FB a better DB than Mysql.

We have the same idea, you are not alone ;)

> I've found this thread on the subject:
>
> http://www.mail-archive.com/firebird-net-provider@.../msg06119.html
>
> which says the problem should be resolved. but as far as i can tell it's not.

It was about .Net provider. Since you used IBPP its not for you ;)

Regards,
Vlad