Exchange 2007 logon failure

Just brought up an Exchange 2007 server next to our working Exchange 2003
server. Moved one user mailbox over to the Exchange 2007 server. Users is
still running Outlook 2003. Outlook would not connect to the Exchange 2007
server. Nothing in client event log. Event log on Exchange 2007 server shows
logon failure for user with event ID 1022.

Researched this a bit and found a suggestion to add SELF account with full
permission under advanced Exchange tab in ADUC. User can now connect to
Exchange 2007 server. I reviewed other user accounts and none have the SELF
account listed. Looks like we will need to change this on all our users
before we move there mailboxes? If the SELF account is needed why wasn't it
added when the account/mailbox was created? Will this happen automatically
under the Exchange 2007 environment?

Craig