GoDaddy, Subject Alternate Name certificates, and Exchange 2007
Exchange 2007 automatically creates "self signed" SSL certificates for CAS and Hub Transport servers. However, if you want to use SSL for OWA/ActiveSync/Autodiscover/Availability, etc... or if you want to do TLS/SSL for SMTP, then you need a publicly trusted certificate. However, this introduces a problem. Internal clients try to use the server name or the internal FQDN and will generate errors if the certificate on the internal HTTP virtual server is issued for an external URL.
The answer is to either create both internal and external virtual directories and use separate SSL certificates for each. This is a bit of a pain in the neck, though.
The Exchange 2007 EMS cmdlet new-ExchangeCertificate can create a certificate request that includes multiple additional server names or FQDNs. These additional FQDNs go in to the Subject Alternate Name field of the certificate.
Not all public certificate authorities will support these. However, GoDaddy has come out with a new certificate called a 6-in-1 certificate for $62.99 per year. This is a great deal and one I will probably be recommending to all of my customers.