right MTA for crypto support

[Eugen Leitl]

I'm getting rather pissed at diverse wiretap legislations making the
global rounds (lately EU is making noises towards storing a one year deep
FIFO of all email and browsing traffic for all users), and would like to
run my own MTA, with MX fallback to ISPs. I would like to have secure
MUA-MTA (IMAP/SSL POP/SSL and MTA-MTA (if the other end supports it).

If anyone knows of patches which automatically query keyservers and
GPG/PGP encrypt emails to targets (this is not a deep paranoia setup, just
a cheap measure to increase encrypted mail traffic) that would be nice to
have, too.

1) Out of Postfix and Exim (no qmail, please), which is the MTA scoring 
   highest on crypto support?

2) Can you give me pointers to suitable crypto patches for above MTAs?

TIA,
Eugen