The email.message_from_file function does not seem to 
work correctly when used as the "factory" argument to 
the mailbox.UnixMailbox function. The "From_" 
separator line gets included in the preceding mail 
message.

For a demonstration of this, see the attached zip file. 
The Python code loads the first message in the mailbox 
file and then displays the final line. This shows the 
From_ line from the subsequent message (correctly 
quoted with a ">"!!!).

This is with Python 2.2 on Windows 2000. The Python 
banner line is

Python 2.2 (#28, Dec 21 2001, 12:21:22) [MSC 32 bit 
(Intel)] on win32