#6 Add option to use PortableUnixMailbox instead of UnixMailbox

[Donovan Baarda]

I have just been hit by a mbox parsing problem that was
fixed by switching to PortableUnixMailbox. I see in the
ChangeLog that you switched from PortableUnixMailbox to
UnixMailbox to fix another parsing problem.

Perhaps there should be an option to use either format?

[Brandon Knitter]

Logged In: YES
user_id=11101

Can you indicate which version this was changed in so that I
can see if a switch would be available?

Sorry, just took over this project.