I've been using claws-mail with my IMAP server. I'm giving
thunderbird a try but it won't work if I have "Use secure
authentication" checked under "Server Settings". I thought I had
configured the server to use secure authentication only. Here is some
of my /etc/postfix/main.cf:

smtpd_sasl_auth_enable = yes
smtpd_sasl2_auth_enable = yes
smtpd_sasl_security_options = noanonymous
smtpd_sasl_local_domain =

smtpd_recipient_restrictions =
    permit_sasl_authenticated,
    permit_mynetworks,
    check_policy_service inet:127.0.0.1:10030
    reject_unauth_destination,
    permit

virtual_alias_maps = hash:/etc/postfix/virtual

message_size_limit = 20480000

smtpd_tls_security_level = may
smtpd_tls_auth_only = yes
smtpd_tls_key_file = /etc/ssl/postfix/server.key
smtpd_tls_cert_file = /etc/ssl/postfix/server.crt
smtpd_tls_CAfile = /etc/ssl/postfix/server.pem
smtpd_tls_session_cache_timeout = 3600s
tls_random_source = dev:/dev/urandom

- Grant
--
gentoo-user@(protected)