I'm using procmail to filter my mailing list mail into seperate IMAP mailboxes. I'd like to label some of these so they will appear in a different client in thunderbird, using procmail rules. I've see references to X-Keywords, but the following doesn't seem to work:
:0 fh w
* ^List-Id: .*
| formail -i "X-Keywords: \$Label3"
The X-Keywords is edited in, but it's not honored. Does anyone have any suggestions as to how to do this?