Hi,
I am happy to announce that this long standing problem has been finally fixed in the ROOT cvs. It was due to a fundamental problem on MacOS X where bool data members are 4 bytes, as opposed to 1 byte on all other known platforms. This caused bools that were true before saving to be false when the object was read back. And this is what caused the problems with the TMD5 objects used by PROOF.
Cheers, Fons.