Keep searching and digging.... I got 14000 google hits for C++ decompiler!
Here's are a commercial decompiler ($1100): Salamander. It looks like you can get a tiral version (or maybe submit trial code over the net).
I found something at The University of Queensland.
There is an article at planet-source-code.com.
You might try searching some hacker sites too.
Oops! JungleCreatures is a C# decompiler.