Description of Problem: When used as delivery agent for postfix, mail spools for new users aren't created. Since postfix doesn't run as root, procmail can't create /var/spool/mail/username if invoked by postfix rather than sendmail. Version-Release number of selected component (if applicable): 3.22-2 Suggested fix: Make procmail setgid and drop privileges right after creating the mail spool and setting sane permissions on it.
procmail is not getting a suid bit - it's not that trustworthy.