> However, I find dovecot deliver (which uses the sieve language > for filtering) to be much more readable/writable than procmail.
Sieve does not include regular expressions -- I shit you not. Dovecote needs regular expression capability to be shoe-horned in by some hokey plugin. Regular expressions are quite fundamental to a mail filtering language that has an appropriate amount of expressive power. It's bizarre that sieve is presented as a thought out successor to procmail complete with an RFC, and yet it excludes something as essential as regular expressions. I'm resisting sieve because the C-style makes the code look cluttered, and it lacks expressive power. The one aspect that may compel a switch to sieve is the fact that it is MIME-aware. MIME predates procmail, and it's a shame that procmail has become unmaintained. OTOH, I might rather have third party tools for MIME than third party tools for regular expressions.
