I'm trying to use stunnel to send email with SSL authentication.

Sending the email with Apple's Mail.app with 'use default ports' selected. 

stunnel.log output:

2009.06.12 09:58:17 LOG7[41897:140735078037248]: Snagged 64 random bytes from /Users/jlbrown/.rnd
2009.06.12 09:58:17 LOG7[41897:140735078037248]: Wrote 1024 new random bytes to /Users/jlbrown/.rnd
2009.06.12 09:58:17 LOG7[41897:140735078037248]: RAND_status claims sufficient entropy for the PRNG
2009.06.12 09:58:17 LOG7[41897:140735078037248]: PRNG seeded successfully
2009.06.12 09:58:17 LOG7[41897:140735078037248]: Certificate: /etc/postfix/smtpd.cert
2009.06.12 09:58:17 LOG7[41897:140735078037248]: Certificate loaded
2009.06.12 09:58:17 LOG7[41897:140735078037248]: Key file: /etc/postfix/smtpd.key
2009.06.12 09:58:17 LOG7[41897:140735078037248]: Private key loaded
2009.06.12 09:58:17 LOG7[41897:140735078037248]: SSL context initialized for service ssmtp
2009.06.12 09:58:17 LOG7[41897:140735078037248]: Certificate: /etc/postfix/smtpd.cert
2009.06.12 09:58:17 LOG7[41897:140735078037248]: Certificate loaded
2009.06.12 09:58:17 LOG7[41897:140735078037248]: Key file: /etc/postfix/smtpd.key
2009.06.12 09:58:17 LOG7[41897:140735078037248]: Private key loaded
2009.06.12 09:58:17 LOG7[41897:140735078037248]: SSL context initialized for service ssmtp2
2009.06.12 09:58:17 LOG5[41897:140735078037248]: stunnel 4.27 on i686-apple-darwin9.7.0 with OpenSSL 0.9.7l 28 Sep 2006
2009.06.12 09:58:17 LOG5[41897:140735078037248]: Threading:PTHREAD SSL:ENGINE Sockets:SELECT,IPv6 Auth:LIBWRAP
2009.06.12 09:58:17 LOG6[41897:140735078037248]: file ulimit = 256 (can be changed with 'ulimit -n')
2009.06.12 09:58:17 LOG6[41897:140735078037248]: FD_SETSIZE = 1024 (some systems allow to increase this value)
2009.06.12 09:58:17 LOG5[41897:140735078037248]: 125 clients allowed
2009.06.12 09:58:17 LOG7[41897:140735078037248]: FD 10 in non-blocking mode
2009.06.12 09:58:17 LOG7[41897:140735078037248]: FD 11 in non-blocking mode
2009.06.12 09:58:17 LOG7[41897:140735078037248]: FD 12 in non-blocking mode
2009.06.12 09:58:17 LOG7[41897:140735078037248]: SO_REUSEADDR option set on accept socket
2009.06.12 09:58:17 LOG7[41897:140735078037248]: ssmtp bound to 0.0.0.0:465
2009.06.12 09:58:17 LOG7[41897:140735078037248]: FD 13 in non-blocking mode
2009.06.12 09:58:17 LOG7[41897:140735078037248]: SO_REUSEADDR option set on accept socket
2009.06.12 09:58:17 LOG7[41897:140735078037248]: ssmtp2 bound to 0.0.0.0:587
2009.06.12 09:58:17 LOG7[41903:140735078037248]: Created pid file /usr/local/var/run/stunnel/stunnel.pid
2009.06.12 09:58:56 LOG7[41903:140735078037248]: ssmtp2 accepted FD=14 from 192.168.1.10:64996
2009.06.12 09:58:56 LOG7[41903:4295561216]: ssmtp2 started
2009.06.12 09:58:56 LOG7[41903:4295561216]: FD 14 in non-blocking mode
2009.06.12 09:58:56 LOG7[41903:4295561216]: TCP_NODELAY option set on local socket
2009.06.12 09:58:56 LOG7[41903:4295561216]: Waiting for a libwrap process
2009.06.12 09:58:56 LOG7[41903:4295561216]: Acquired libwrap process #0
2009.06.12 10:00:04 LOG7[41903:140735078037248]: ssmtp2 accepted FD=15 from 192.168.1.10:65006
2009.06.12 10:00:04 LOG7[41903:4295675904]: ssmtp2 started
2009.06.12 10:00:04 LOG7[41903:4295675904]: FD 15 in non-blocking mode
2009.06.12 10:00:04 LOG7[41903:4295675904]: TCP_NODELAY option set on local socket
2009.06.12 10:00:04 LOG7[41903:4295675904]: Waiting for a libwrap process
2009.06.12 10:00:04 LOG7[41903:4295675904]: Acquired libwrap process #1
2009.06.12 10:01:04 LOG7[41903:140735078037248]: ssmtp accepted FD=16 from 192.168.1.10:65013
2009.06.12 10:01:04 LOG7[41903:4295790592]: ssmtp started
2009.06.12 10:01:04 LOG7[41903:4295790592]: FD 16 in non-blocking mode
2009.06.12 10:01:04 LOG7[41903:4295790592]: TCP_NODELAY option set on local socket
2009.06.12 10:01:04 LOG7[41903:4295790592]: Waiting for a libwrap process
2009.06.12 10:01:04 LOG7[41903:4295790592]: Acquired libwrap process #2
2009.06.12 10:03:56 LOG6[41903:4295561216]: read_blocking: s_poll_wait timeout
2009.06.12 10:03:56 LOG5[41903:4295561216]: Connection reset: 0 bytes sent to SSL, 0 bytes sent to socket
2009.06.12 10:03:56 LOG7[41903:4295561216]: ssmtp2 finished (2 left)
2009.06.12 10:03:56 LOG7[41903:140735078037248]: ssmtp accepted FD=14 from 192.168.1.10:65022
2009.06.12 10:03:56 LOG7[41903:4295561216]: ssmtp started
2009.06.12 10:03:56 LOG7[41903:4295561216]: FD 14 in non-blocking mode
2009.06.12 10:03:56 LOG7[41903:4295561216]: TCP_NODELAY option set on local socket
2009.06.12 10:03:56 LOG7[41903:4295561216]: Waiting for a libwrap process
2009.06.12 10:03:56 LOG7[41903:4295561216]: Acquired libwrap process #3
2009.06.12 10:05:04 LOG6[41903:4295675904]: read_blocking: s_poll_wait timeout
2009.06.12 10:05:04 LOG5[41903:4295675904]: Connection reset: 0 bytes sent to SSL, 0 bytes sent to socket
2009.06.12 10:05:04 LOG7[41903:4295675904]: ssmtp2 finished (2 left)
2009.06.12 10:05:04 LOG7[41903:140735078037248]: ssmtp accepted FD=15 from 192.168.1.10:65028
2009.06.12 10:05:04 LOG7[41903:4295675904]: ssmtp started
2009.06.12 10:05:04 LOG7[41903:4295675904]: FD 15 in non-blocking mode
2009.06.12 10:05:04 LOG7[41903:4295675904]: TCP_NODELAY option set on local socket
2009.06.12 10:05:04 LOG7[41903:4295675904]: Waiting for a libwrap process
2009.06.12 10:05:04 LOG7[41903:4295675904]: Acquired libwrap process #4
2009.06.12 10:06:04 LOG6[41903:4295790592]: read_blocking: s_poll_wait timeout
2009.06.12 10:06:04 LOG5[41903:4295790592]: Connection reset: 0 bytes sent to SSL, 0 bytes sent to socket
2009.06.12 10:06:04 LOG7[41903:4295790592]: ssmtp finished (2 left)
2009.06.12 10:06:04 LOG7[41903:140735078037248]: ssmtp accepted FD=16 from 192.168.1.10:65032
2009.06.12 10:06:04 LOG7[41903:4295790592]: ssmtp started
2009.06.12 10:06:04 LOG7[41903:4295790592]: FD 16 in non-blocking mode
2009.06.12 10:06:04 LOG7[41903:4295790592]: TCP_NODELAY option set on local socket
2009.06.12 10:06:04 LOG7[41903:4295790592]: Waiting for a libwrap process
2009.06.12 10:08:56 LOG6[41903:4295561216]: read_blocking: s_poll_wait timeout
2009.06.12 10:08:56 LOG5[41903:4295561216]: Connection reset: 0 bytes sent to SSL, 0 bytes sent to socket
2009.06.12 10:08:56 LOG7[41903:4295561216]: ssmtp finished (2 left)
2009.06.12 10:08:56 LOG7[41903:140735078037248]: ssmtp2 accepted FD=14 from 192.168.1.10:65040
2009.06.12 10:08:56 LOG7[41903:4295561216]: ssmtp2 started
2009.06.12 10:08:56 LOG7[41903:4295561216]: FD 14 in non-blocking mode
2009.06.12 10:08:56 LOG7[41903:4295561216]: TCP_NODELAY option set on local socket
2009.06.12 10:08:56 LOG7[41903:4295561216]: Waiting for a libwrap process
2009.06.12 10:10:04 LOG6[41903:4295675904]: read_blocking: s_poll_wait timeout
2009.06.12 10:10:04 LOG5[41903:4295675904]: Connection reset: 0 bytes sent to SSL, 0 bytes sent to socket
2009.06.12 10:10:04 LOG7[41903:4295675904]: ssmtp finished (2 left)
2009.06.12 10:10:04 LOG7[41903:140735078037248]: ssmtp accepted FD=15 from 192.168.1.10:65044
2009.06.12 10:10:04 LOG7[41903:4295675904]: ssmtp started
2009.06.12 10:10:04 LOG7[41903:4295675904]: FD 15 in non-blocking mode
2009.06.12 10:10:04 LOG7[41903:4295675904]: TCP_NODELAY option set on local socket
2009.06.12 10:10:04 LOG7[41903:4295675904]: Waiting for a libwrap process
2009.06.12 10:11:04 LOG7[41903:140735078037248]: ssmtp accepted FD=17 from 192.168.1.10:65048
2009.06.12 10:11:04 LOG7[41903:4295905280]: ssmtp started
2009.06.12 10:11:04 LOG7[41903:4295905280]: FD 17 in non-blocking mode
2009.06.12 10:11:04 LOG7[41903:4295905280]: TCP_NODELAY option set on local socket
2009.06.12 10:11:04 LOG7[41903:4295905280]: Waiting for a libwrap process
2009.06.12 10:13:56 LOG7[41903:140735078037248]: ssmtp accepted FD=18 from 192.168.1.10:65060
2009.06.12 10:13:56 LOG7[41903:4297134080]: ssmtp started
2009.06.12 10:13:56 LOG7[41903:4297134080]: FD 18 in non-blocking mode
2009.06.12 10:13:56 LOG7[41903:4297134080]: TCP_NODELAY option set on local socket
2009.06.12 10:13:56 LOG7[41903:4297134080]: Waiting for a libwrap process
2009.06.12 10:15:04 LOG7[41903:140735078037248]: ssmtp accepted FD=19 from 192.168.1.10:65063
2009.06.12 10:15:04 LOG7[41903:4297211904]: ssmtp started
2009.06.12 10:15:04 LOG7[41903:4297211904]: FD 19 in non-blocking mode
2009.06.12 10:15:04 LOG7[41903:4297211904]: TCP_NODELAY option set on local socket
2009.06.12 10:15:04 LOG7[41903:4297211904]: Waiting for a libwrap process
2009.06.12 10:18:56 LOG7[41903:140735078037248]: ssmtp2 accepted FD=20 from 192.168.1.10:65090
2009.06.12 10:18:56 LOG7[41903:4297326592]: ssmtp2 started
2009.06.12 10:18:56 LOG7[41903:4297326592]: FD 20 in non-blocking mode
2009.06.12 10:18:56 LOG7[41903:4297326592]: TCP_NODELAY option set on local socket
2009.06.12 10:18:56 LOG7[41903:4297326592]: Waiting for a libwrap process
2009.06.12 10:20:04 LOG7[41903:140735078037248]: ssmtp2 accepted FD=21 from 192.168.1.10:65093
2009.06.12 10:20:04 LOG7[41903:4297441280]: ssmtp2 started
2009.06.12 10:20:04 LOG7[41903:4297441280]: FD 21 in non-blocking mode
2009.06.12 10:20:04 LOG7[41903:4297441280]: TCP_NODELAY option set on local socket
2009.06.12 10:20:04 LOG7[41903:4297441280]: Waiting for a libwrap process
2009.06.12 10:23:56 LOG7[41903:140735078037248]: ssmtp2 accepted FD=22 from 192.168.1.10:65111
2009.06.12 10:23:56 LOG7[41903:4297555968]: ssmtp2 started
2009.06.12 10:23:56 LOG7[41903:4297555968]: FD 22 in non-blocking mode
2009.06.12 10:23:56 LOG7[41903:4297555968]: TCP_NODELAY option set on local socket
2009.06.12 10:23:56 LOG7[41903:4297555968]: Waiting for a libwrap process
2009.06.12 10:25:04 LOG7[41903:140735078037248]: ssmtp accepted FD=23 from 192.168.1.10:65113
2009.06.12 10:25:04 LOG7[41903:4297670656]: ssmtp started
2009.06.12 10:25:04 LOG7[41903:4297670656]: FD 23 in non-blocking mode
2009.06.12 10:25:04 LOG7[41903:4297670656]: TCP_NODELAY option set on local socket
2009.06.12 10:25:04 LOG7[41903:4297670656]: Waiting for a libwrap process
2009.06.12 10:28:56 LOG7[41903:140735078037248]: ssmtp2 accepted FD=24 from 192.168.1.10:65125
2009.06.12 10:28:56 LOG7[41903:4297785344]: ssmtp2 started
2009.06.12 10:28:56 LOG7[41903:4297785344]: FD 24 in non-blocking mode
2009.06.12 10:28:56 LOG7[41903:4297785344]: TCP_NODELAY option set on local socket
2009.06.12 10:28:56 LOG7[41903:4297785344]: Waiting for a libwrap process
2009.06.12 10:30:04 LOG7[41903:140735078037248]: ssmtp2 accepted FD=25 from 192.168.1.10:65128
2009.06.12 10:30:04 LOG7[41903:4297900032]: ssmtp2 started
2009.06.12 10:30:04 LOG7[41903:4297900032]: FD 25 in non-blocking mode
2009.06.12 10:30:04 LOG7[41903:4297900032]: TCP_NODELAY option set on local socket
2009.06.12 10:30:04 LOG7[41903:4297900032]: Waiting for a libwrap process
2009.06.12 10:33:56 LOG7[41903:140735078037248]: ssmtp2 accepted FD=26 from 192.168.1.10:65299
2009.06.12 10:33:56 LOG7[41903:4298014720]: ssmtp2 started
2009.06.12 10:33:56 LOG7[41903:4298014720]: FD 26 in non-blocking mode
2009.06.12 10:33:56 LOG7[41903:4298014720]: TCP_NODELAY option set on local socket
2009.06.12 10:33:56 LOG7[41903:4298014720]: Waiting for a libwrap process
2009.06.12 10:35:04 LOG7[41903:140735078037248]: ssmtp2 accepted FD=27 from 192.168.1.10:65326
2009.06.12 10:35:04 LOG7[41903:4298129408]: ssmtp2 started
2009.06.12 10:35:04 LOG7[41903:4298129408]: FD 27 in non-blocking mode
2009.06.12 10:35:04 LOG7[41903:4298129408]: TCP_NODELAY option set on local socket
2009.06.12 10:35:04 LOG7[41903:4298129408]: Waiting for a libwrap process
2009.06.12 10:40:04 LOG7[41903:140735078037248]: ssmtp accepted FD=28 from 192.168.1.10:65365
2009.06.12 10:40:04 LOG7[41903:4298244096]: ssmtp started
2009.06.12 10:40:04 LOG7[41903:4298244096]: FD 28 in non-blocking mode
2009.06.12 10:40:04 LOG7[41903:4298244096]: TCP_NODELAY option set on local socket
2009.06.12 10:40:04 LOG7[41903:4298244096]: Waiting for a libwrap process
2009.06.12 10:45:04 LOG7[41903:140735078037248]: ssmtp accepted FD=29 from 192.168.1.10:65377
2009.06.12 10:45:04 LOG7[41903:4298358784]: ssmtp started
2009.06.12 10:45:04 LOG7[41903:4298358784]: FD 29 in non-blocking mode
2009.06.12 10:45:04 LOG7[41903:4298358784]: TCP_NODELAY option set on local socket
2009.06.12 10:45:04 LOG7[41903:4298358784]: Waiting for a libwrap process
2009.06.12 10:50:04 LOG7[41903:140735078037248]: ssmtp accepted FD=30 from 192.168.1.10:65406
2009.06.12 10:50:04 LOG7[41903:4298473472]: ssmtp started
2009.06.12 10:50:04 LOG7[41903:4298473472]: FD 30 in non-blocking mode
2009.06.12 10:50:04 LOG7[41903:4298473472]: TCP_NODELAY option set on local socket
2009.06.12 10:50:04 LOG7[41903:4298473472]: Waiting for a libwrap process

Stunnel is running on Mac OS X 10.5.7.

Any help would be much appreciated.

James.