I'm having a problem getting SSL to work with SOGo and ActiveSync.

In Apache I redirect everything to SSL in 000-default.conf:

<VirtualHost *:80>
ServerName mail.mydomain.com
Redirect permanent / https://mail.mydomain.com/
</VirtualHost>

This works great for everything but SOGo.
For SOGo, login page loads https correctly, but as soon as you login you end up getting redirected to http and the page doesn't load properly because of mixed http and https calls.
After getting redirected to http I can I can add "https:" in the URL bar and force it, then it will load correctly.

I think the problem is the http ProxyPass statements in the Apache SOGo.conf file:

ProxyPass /Microsoft-Server-ActiveSync \
 http://127.0.0.1:20000/SOGo/Microsoft-Server-ActiveSync \
 retry=60 connectiontimeout=5 timeout=3540

ProxyPass /SOGo http://127.0.0.1:20000/SOGo retry=0

I have tried changing these ProxyPass statements to https (and turning on SSLProxyEngine).
This failed.
I have also changed 127.0.0.1 to mail.mydomain.com (which resolves locally to 127.0.0.1) and this still fails with internal server error.

How can I force SSL for everything?

==== Required information ====
- iRedMail version (check /etc/iredmail-release): 0.9.5.1
- Linux/BSD distribution name and version: Ubuntu 14.04
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL
- Web server (Apache or Nginx): Apache
- Manage mail accounts with iRedAdmin-Pro?
- Related log if you're reporting an issue:
====