mailbox.mbox not locking mbox properly

[Chris Jewell]

Even if you replace the python mbox code with something that uses
fcntl.flock() to protect against concurrent updating, you should also
understand that NFS does *not* provide full Unix filesystem semantics.
In particular, Unix flock(2) (which Python's fcntl.flock() wraps)
doesn't work over NFS.

That's why if you want to access mail over NFS, you should use maildir,
rather than mbox, no matter what your programming language.

-- 
Chris Jewell      chrisj at puffin.com      PO Box 1396 Gualala CA USA 95445-1396