[Dovecot] No ports listening

[Marco]

Please forgive my newbie post but this has me stumped.  I've been a happy
Dovecot 0.X and 1.X admin for years but something in my first 2.X
configuration is oddly broken.  It loads fine, logs no errors, but
doesn't listen to any network ports!  Thanks in advance for any help.

Marco


 # 2.0.19: /etc/dovecot/dovecot.conf
 # OS: Linux 2.6.35.14 x86_64 Ubuntu 10.10 ext4
 auth_debug = yes
 auth_mechanisms = plain login
 first_valid_gid = 111
 first_valid_uid = 111
 login_greeting = example.com pop/imap ready
 mail_location = mbox:/var/mail/%u.imap:INBOX=/var/mail/%u
 passdb {
   args = scheme=CRYPT username_format=%u /etc/dovecot/users
   driver = passwd-file
 }
 service auth {
   unix_listener /var/spool/postfix/private/auth {
     group = postfix
     mode = 0660
     user = postfix
   }
   unix_listener auth-master {
     mode = 0666
   }
 }
 service imap-login {
   inet_listener imap {
     address = *
     port = 143
   }
   inet_listener imaps {
     address = *
     port = 993
   }
   process_limit = 50
 }
 service pop3-login {
   inet_listener pop3 {
     address = *
     port = 110
   }
   inet_listener pop3s {
     address = *
     port = 995
   }
   process_limit = 50
 }
 ssl_cert = </etc/ssl/mail.example.com.crt
 ssl_key = </etc/ssl/mail.example.com.key
 syslog_facility = local0
 userdb {
   args = username_format=%u /etc/dovecot/users
   driver = passwd-file
 }
 valid_chroot_dirs = /var/mail
 verbose_proctitle = yes
 verbose_ssl = yes
 protocol lda {
   postmaster_address = postmas...@example.com
 }