> Though I don't know how many fd's Firebird SS requires per database,
> I guess that 1024 is large enough for this JBoss application.

Yup...

How easy can this issue be reproduced? If you have to wait not so long,
please add loggin into the driver (though expect log to grow really fast),
it will tell where exactly it crashes.

I have no other ideas to this topic. So far I have seen this error message
when name resolution was not configured correctly. But that was permanent
error.

Sorry.

Roman