Redmine

Hi, there!

Ok, i'm trying to create issue with email.

I've setup the mailbox, it's exchange 2016. It uses STARTTLS.

For testing I'm using this within redmine install directory (where Rakefile is located):

 rake redmine:email:receive_imap RAILS_ENV="production" host=****** starttls=true port=143 username=**** password=**** --trace

Output:

** Invoke redmine:email:receive_imap (first_time)
** Invoke environment (first_time)
** Execute environment
** Execute redmine:email:receive_imap
rake aborted!
OpenSSL::SSL::SSLError: SSL_read: ssl handshake failure
/usr/lib/ruby/2.1.0/openssl/buffering.rb:61:in `sysread'
/usr/lib/ruby/2.1.0/openssl/buffering.rb:61:in `fill_rbuff'
/usr/lib/ruby/2.1.0/openssl/buffering.rb:208:in `gets'
/usr/lib/ruby/2.1.0/net/imap.rb:1167:in `get_response'
/usr/lib/ruby/2.1.0/net/imap.rb:1089:in `receive_responses'
/usr/lib/ruby/2.1.0/net/imap.rb:1075:in `block in initialize'
Tasks: TOP => redmine:email:receive_imap

What is going on? If I understand correctly - my redmine server needs to accept self-signed certificate from my mail server, that's why SSL handshake fails, am I right?
How do I get this working?