I tried to check my assumption I did and check them once more.
Excessive logging could be helpful in some situations, but not always. In my case, it didn't help that much.
With logging you can see, where your assumptions are correct and which of them fail.
My personal solution was Java specific. The Java ClassLoader does not load classes completely since JDK 1.5. In a debug session, it has to be loaded completely. So some variables were not initialized well and the output differed from the normal run.
That reason is very hard to find.
