There are two different "From" addresses associated with a particular mail message. There is the RFC822 "From:" line and then there is the "MAIL FROM" return address that is sent as part of the SMTP conversation. (This is the address recorded in the "From " line at the top of the Plan 9 mbox-format messages. See thread last month.)
The two are not always the same. For example, this message says it is From: <[EMAIL PROTECTED]>, but the SMTP return address is something like [EMAIL PROTECTED], so that if a bounce comes back, it goes to the mailing list software, which uses the last bit to determine which address on the list is bouncing. I would be a little surprised if your ISP is rejecting based on the From: line rather than the SMTP return address, but maybe spammers have driven them to that. The /mail/box/$user/headers file sets RFC822 headers, including the From: header. The upas/smtp arguments set the SMTP return address. As for how to do it "right", editing remotemail sounds fine. The nice thing about upas is you can understand the shell scripts and edit them, instead of having to shoehorn everything into some preordained config file. Russ
