Setting up Exchange 2003 server parallel with a 5.5 server.

I have already setup a Win 2K3 AD server in mixed mode within the NT 4.0 domain.  I still have Exchange 5.5 running and want to setup a Exchange 2003 server.  We only have about 80 mailboxes so I would like to have both Exchange servers up and running and move mailboxes in a gradual process.
I have read about doing a migration and move move mailboxes, but am a little gunshy as I believe some mailboxes may be corrupted and do not want to take the risk of blowing the 5.5 server completely out of the water.
Here is what I am hoping to do:  Setup a new Exchange 2003 server in the same site/domain as the 5.5 server with a different internal IP address.  I will configure the Cisco pix to route email accordingly.  I will then export the users mailbox to a PST file and then import to new server. Then will reconfigure users Outlook to point to the new server.
I know this may be a longer process, but is it possible to do it this way or will I run into problems having 2 Exchange servers within the same domain?  Am I missing any other steps?
Please advise and thanks in advance.
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

This is a good plan....

Here are some other tips:


Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
having two mail servers in the in the same org is a normal part of an exchange migration.
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Windows Server 2003

From novice to tech pro — start learning today.