> Well, I wrote the java code inside a try block and the "catch" block
> print a exception like this:
> ...
> ERROR http-8080-Processor25
> org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/expert].[a
> ction] - Servlet.service() for servlet action threw exception
> java.lang.NoClassDefFoundError: javax/transaction/SystemException
> ...
> What's going on with the hibernate? What did I write wrong?
> ...
> I think firebird and hibernate have some problem with "native" id
> declaration. But I don't know if I'm right.

Very likely you're wrong. So far I have no problem with Hibernate and
Firebird. However, the exception stack trace says that you have
configuration problem.

Please ensure that you have included jta.jar from %HIBERNATE_HOME%\lib
directory. However it is not yet me clear why this class is needed...

But please try asking in Hibernate forums.

Roman