> It seems we are finding that Firebird 1.5 is loosing its connections,
> randomly.

Which platform are you running on the clients and server? If its xp sp2
you could be running in to the hard limit imposed on the number of tcp
connections. This can apply on either the server or client, but in most
cases its the client that closes the connection.

You can apply a patch which can be found here http://www.lvllord.de/
to change that setting from 10 to whatever you like, they suggest 100.

Regards
Gary