JDK 1.5 and Objectstore (PSE PRO)

I've be compiling my application with JDK 1.4 and using 1.3 for binding those classes for Objectstore. I recently upgraded to JDK 1.5 (1.5.0_06) and the binding (persist) does not work now. I get the following message for all classes I'm try to bind:

Error: xxx.class is not a valid class file.

If I simply change back to JDK 1.4 (1.4.2_04), it works. I'm also using ANT 1.6.2 to build.

Does anybody have any idea as to whta is the conflict?

Thanks.

[490 byte] By [gnorketta] at [2007-10-2 19:25:07]