I'm in the process of trying to properly construct the migration from an Exchange 2003 forest. The destination is a new Greenfield Server 2008/Exchange 2007 forest. The existing URL for OWA access in the 2003 forest is "mail.domain.com".
The new forest will be configured as "webmail.domain.com". However, for the simplicity of the users, we'd like to keep their URL knowledge to "mail.domain.com".
The complication is that we'd need to coexist with both environments for months before getting rid of the old 2003 email environment. I'm looking to see if it's possible to do this (at this time, I don't think it's possible). Any advice or thoughts would be appreciated!