When using procmail DEFAULT is not being read from either /etc/procmailrc or ~/.procmailrc, at least this is the case with delivery to MAILDIR style mailboxes. Grant Goodyear <g2boojum@gentoo.org> writes (in Changelog): "Thanks to Jose Fonseca procmail now uses /etc/procmailrc to determine the default mailbox instead of patching the source." Using DEFAULT=$HOME/.maildir/ i get: procmail: Couldn't create "/var/spool/mail/unit" (where "unit" is $USER) This suggests this isn't the case. The value MAILSPOOLDIR ("/var/spool/mail/") seems to be used as MAILSPOOLHOME isn't defined (see: src/authenticate.c). In fact, for Maildir delivery MAILSPOOLDIR shouldn't be defined only MAILSPOOLHOME (at least that the way i have always installed procmail for use with Maildir). The only solution i can think of is to patch authenticate.c based on USE="maildir" (as mbox won't be an issue). This is somewhat problematic as most users won't have maildir (or mbox for that matter) defined. I plan on bumping the ebuild to r3 (and masking for the present time).
-r4 has been in portage for some time (unmasked).
