I see.  Indeed, in the callback situation the 2.5 change
is not very good.  On the other hand, I have a (possibly
more obscure) case where the new equality makes more
sense.  Note also that the change was meant to unify
the behavior of built-in and user method objects; e.g.
if you use callbacks as dict keys, then already in
previous Python versions it was impossible to use say
'mylist.append' as a callback.  Moreover, the hash of
user methods was strangely based on the hash of the
object itself already, which made dict key collisions
likely.

All in all I think that this part was an accident
and never designed; I won't pronounce myself and
suggest that python-dev should decide which of the
two behaviors is realy "expected".