See:
http://www.squirrelmail.org/docs/adm...n-8.html#ss8.3
You can place all your SSL directives in your main httpd.conf file, or in a separate httpd-ssl.conf file, which you include in your httpd.conf file (to reduce clutter). Eg:
httpd.conf:
....
# Secure (SSL/TLS) connections
# simple mod_rewrite example
Include etc/httpd/httpd-ssl.conf
I have a regular http virtual host which re-directs to https:
httpd-vhosts.conf:
...
<VirtualHost *:80>
...
RewriteEngine on
RewriteCond %{HTTPS} !=on
RewriteRule .* https://%{HTTP_HOST}:443%{REQUEST_URI} [QSA,R=permanent,L]
...
</VirtualHost>
but you can use any of the methods suggested in the URL above.
The exchange happens automatically when a client connects to the HTTPS port - that's why there is a separate listener port (443 vs. 80). This happens behind the scenes once you have the HTTPS listener configured.
If SSLEngine is found to be invalid, check to be sure you have an SSL-compiled http daemon.