Emailer Custom Mail Headers
(an unsupported* feature hack to Emailer 2.0)

It is possible to include custom headers in the messages that you send from Emailer. There are many reasons why one might want to do this. If you currently don't know why, then you most likely do not need to do this...

OK, here's an example: you might want to include a Precedence: List header so that messages you send to large groups can be processed by the recipients (they could have a mail action that sets list mail to a low priority).

How it works

The hack works by adding your new custom headers to an existing header field in Emailer. The existing header field, x-mailer , is included in all outgoing messages that you send. Therefore, all of the new headers that you add are also included in all of your outgoing messages.

Important: If you wish to send different headers for some messages (such as those sent from a home account vs. a work account), you will need to create two copies of the Emailer application, and modify each copy individually.

How to do it

  1. Open a copy of the Emailer application in a Resource Editor such as Apple's ResEdit (free on many FTP sites) or Resourcerer
  2. Open the STR# resources
  3. Open the STR# resource ID 3400
  4. Scroll down to #35
  5. Place the cursor to the right of " ^0 " in the text field
  6. Insert a CRLF (Carriage Return, Line Feed) by pressing Control-M and then Control-J
  7. Type in your desired header and value (i.e. Precedence: List )

    To add additional headers, Repeat steps 6 and 7 until all desired headers have been added.

    Important: Each resource text field can only accept up to 255 characters of text (including CR and LF characters). If you need to add more headers than that, you can use field #35 , x-sender , in a similar manner.
    Important: Make sure you do not put and control characters (such as CR or LF characters) at the end of the text field. This will make your messages unreadable by any mail server.
  8. Press Cmd-S to save your changes

From now on, every message you send with this copy of Emailer will contain the new header(s).

*Apparently Necessary Legal Stuff
This package is not released and not supported by Claris Corporation in any way (real or imaginary) at any point in time (past, present, and future). Use of these files and information contained within is entirely at the risk of that user, and I, Claris, Fog City, and everyone else you would like to blame will not be held responsible. Unless, of course, the result is positive (i.e. achieving greater productivity, winning the lottery, establishing world peace, ...) in which case I will gladly take some of the credit :-)

David Cortright