> 18:08:52,025 WARN [ServiceController] Problem starting service
> jboss.j2ee:jndiName=jndi/CityBean,service=EJB
> java.lang.IncompatibleClassChangeError
> at org.firebirdsql.jdbc.FBStringField.setString
> (FBStringField.java:288)}
> ....
> I have also tried stable versions of all the above mentioned
> products and still get the same error.
>
> I'm new to EBJ, JBoss and Firebird.

Try to rebuild the driver using JDK you use to run JBoss.

If this does not help, try asking this in JBoss forum. Recently they
were doing a lot of interesting stuff by modifying byte-code on the
fly, and this might be one of the consequences.

Best regards,
Roman Rokytskyy