I spent several hours this evening beating my head against a wall of IDL-Java ignorance. Ive been trying to generate Java stubs for Berlin's main library and all idl-java compilers I tried either choked on the idl or generated non- compilable code. At some point it became clear to me that a) I won't find a compiler/ORB that 'just works' b) I won't be able to understand IDL well just by reading generated Java code and trying to work backwards. I sat myself down with the IDL spec and the IDL-Java mapping spec, learned both by heart, generated a bunch of IDL test cases, fed them through the closest-to-working idl compiler (jacORB's), stared at the compiler's source code, picked a class for closer inspection and almost immediately found the problem. It wasn't hard, what I was doing earlier was hard - searching for solutions in the places that I was comfortable with instead of the places most likely to contain the problem. This is a general pitfall, worth looking out for. Practical example - suppose you're walking home at night, somewhat inebriated. You reach the entrance of your house, only to realize you've lost your keys. You may feel the urge to start looking for them on the ground under nearby streetlights - you can see better there. Resist it. At the very least, try the door.