The name of the security certificate is invalid or does not match the name of the site - exchange 2007 & 2010 coexistence

I'm having the same issue as described in http://social.technet.microsoft.com/Forums/en/exchange2010/thread/ad2a834f-e326-48f2-8ed2-6b8e7e840fba

But when I do the cert export, it has all the services listed: IMAP, POP, IIS, SMTP.

This is the same scenario. Internal outlook 2007 or 2010 users both get this message.

Everything else in the environment is coexisting as it should apparently.

Thanks,

Josh