[Dovecot] imaps only, and on a nonstandard port?

[Dan Stromberg]

I'm trying to get dovecot configured to:

1) Only do imaps
2) Do imaps on port 500

I've tried "ssl_listen = *:500" both globally and in my "protocol imap"
section, but neither seems to be working.

Is there a way of doing this?

Thanks!