Is this all the code, and are you sure there are no differences? That's the first step.
Then, the only thing I could think of is to check to see if your compiler by passes certain things - check your settings for that, but that's a long shot (I'm Guessing). Look here for the docs page and compare again.
http://java.sun.com/j2se/1.5.0/docs/...ang.Object...)
Sorry I can't help ya more bud.