Hey guys, as mentioned in my previous post, my ZCS is now active. I've run into some issues today (24 hrs of being active) and I was hoping to get some help please:

1. How do I set it up to use POPS (secured POP)? Or, is TLS better? If so, how do I setup TLS?

2. I have my mail server setup at mail.redcarpetfinancial.ca and I have emails for other domains too. For example, let's say I have a domain at hidden-domain.com and I have an email address there of me@hidden-domain.com. I have setup my DNS records to mail.hidden-domain.com to point to ZCS. The problem is that when you connect with the SMTP client or the POP client it prompts a security exception because ZCS created an SSL certificate that is for mail.redcarpetfinancial.ca. Is there a way to have it create (hopefully automatically) a new SSL certificate whenever a new account is added from an external domain name?

3. I received a bounced message today. I have emailed this person many many times so I don't know why it would have been all of a sudden rejected, but could someone please take a look at the bounce error message and see if there is anything that I can do to fix it? (I have removed the email addresses so that the spam bots don't pick up the addresses).
Code:
This is the mail system at host mail.redcarpetfinancial.ca.

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

                   The mail system

<hidden@hidden.com>: host mx10.hidden-domain.com[xxx.xxx.xxx.xxx] said: 554
    5.7.1 <me@email.com>: Sender address rejected: Access denied (in
    reply to RCPT TO command)



Reporting-MTA: dns; mail.redcarpetfinancial.ca
X-Postfix-Queue-ID: B13E5127C7A
X-Postfix-Sender: rfc822; me@email.com
Arrival-Date: Mon,  9 Jan 2012 16:31:10 -0500 (EST)

Final-Recipient: rfc822; hidden@hidden.com
Original-Recipient: rfc822;hidden@hidden.com
Action: failed
Status: 5.7.1
Remote-MTA: dns; mx10.hidden-domain.com
Diagnostic-Code: smtp; 554 5.7.1 <me@email.com>: Sender address
    rejected: Access denied