Outlook Anywhere

Hello,

I want to publish Outlook Anywhere (Exchange 2010) thorugh our UTM and it works gread with the steps in the official documentation (Sophos UTM Web Application Firewall for Microsoft Exchange Services). Now, I have a few question regarding this setup:

- What exactly happens when I activate "Pass Outlook Anywhere"? Does the UTM check if it's a Outlook Anywhere connection and that's all?
- The documentation says that I should use the same certificate as it is installed on the Exchange Server. Is that really necessary? Today I use a Microsoft enterprise CA for internal certificates but I want to use a public certificate on the UTM. I know that the public dns name has to be on the SAN certificate on our Exchange server.
- Is there a way to do a preauthentication? I don't want to allow all users to use Outlook Anywhere, I know I can disable it on the Exchange server but is it also possible with the UTM?
- Do I have to publish Autodiscover or OAB as well?

Thanks and kind regards