We have both Certified Interbase 6 and Firebird running on different
machine. What is the best way for Java application to work for both
Database?

If I use Borland Interclient, it only works with Borland InterServer
on Borland Interbase, not firebird. The error is:

SQL State: ICJH2
Error Code: 6
Message: [interclient] Installed versions of InterClient and
InterServer use incompatible client/server protocol versions.
See API reference for exception
interbase.interclient.BadInstallationException

The good news is that Firebird type 4 JDBC works with both. It seems
that this driver is incomplete and I don't like to use it on a
production environment.

Any suggestions?

jw