I was pointed out to a problem with the 'threading' module; when you use it,
the functions running in the threads are sometimes not Psyco-accelerated (but
they sometimes are -- nothing quite consistent).
The problem turned out to be that 'threading' makes a local copy of
'thread.start_new_thread', a function which Psyco needs to patch with its own
version. So if you actually do
it works nicely :-)
I have of course fixed the problem (together with another related problem) in
the latest CVS version.