CRTJVAPGM - then run problem

Hi,
    I wonder if anyone can help with respect to this command.

    I recently downloaded some software that makes use of classes in a
jar file when converting data from a database file to excel. This
utilises RPG and java.

    As process quite slow when running, I tried using CRTJVAPGM at
level 40 optimisation to speed up process.

    When CRTJVAPGM had run over jar file and conversion process re-run,
a single page print out was created in job stating that java program
was not used. Apologies I haven't got error message or id to hand, will
post monday when back at work.

    Wondered if anyone had come across this issue before and could help
in resolving it.

    I should point out that I made no modifications to RPG that ran
classes from jar file, was hoping that process would just start using
optimised program.

    I realise I'm most probably being rather obtuse, but any feedback
would be gratefully received. Feedback kept as simple as possible as no
java experience at all.

Regards

Ian