ORO 2.0.7 & WebSphere 5.1 ...substitute() method not found

There was a brief thread here a year or so ago RE:
WAS reporting a missing ORO substitute() method.
I haven't had that problem until the recent WAS 5.1
release; now I can't can't seem to get WAS to load
the *real* ORO package. I've seen a couple of
posts (via Google) about changing the class loading
sequence, but that doesn't seem to correct the problem.

has anyone managed to get WAS 5.1 to load the real
ORO ? Any hints much appreciated.

TIA,
Dean Arnold