In the newest commit, I added returning mails and support for auction house mails (since they auto-delete).
I also added a sledgehammer function called PurgeMail that will attempt to stip an email and delete it.
I also uploaded GMail stub to branch that contains GMail Express. It enables expressmail shortcuts that use the atomic functions of Postal in the inbox. It also remembers the last person you mailed and autofills it. GMail Express is going to be the "mail tweaks" mod for things like "autofill subject with money/item" type things people expect in a good mailmod.