Hmmm. Sticky problem.
Here is a suggestion. I can't guarantee it will work.
Establish a trust between NT4 and the W2K forest. Now repermission your 5.5
mailboxes with the W2K user accounts. You should be able to do this quickly
with a CSV import. Try it on a test user first.
After you repermsion the mailboxes, you can follow a regular E2K migration
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