Postilion is a mail user agent based on the popular TkRat program.
The main changes to TkRat are in the user interface portion, so all of the underlying functionality of TkRat remains. This includes MIME support, virtual folders, PGP support, support for UNIX mail files, MH folders, POP and IMAP. For a full list of TkRat's features see the TkRat Web page.
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