I have been working on upgrading my mailserver from 10.1.5 to 10.2 and have run into an annoying problem. I followed the sendmail article by Chris Stone of MacDevCenter for enbling sendmail in 10.1.5. Apple has fixed the mail services startup script and the ownership of the clientmqueue directory; so these steps are no longer necessary. However, all received messages have the "F" in the From header chopped off, corrupting the entire INBOX after that point. One more strange point - I have procmail process certain messages before things land in my INBOX (e.g., mailing list msgs are filed in alternate mailboxes); these messages don't seem to be corrupted; however, turning off procmail completely doesn't solve the INBOX problem.
I used procmail to hack a workaround until I can figure out what is going on. After all my other rules process, I send the messages destined for the INBOX through a sed filter which changes the "rom" in the first header line back to "From". Here is the recipe I used at the end of ~/.procmailrc:
# Fix truncated "From" headerThis sed function takes just line 1 (the From header is always the first line) and converts any "rom" string at the beginning of the line to "From".
:0fhw
| sed '1 s/^rom/From/'
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