Adding a User from One Domain to a Group in Another Domain

I have 2 W2K3 domains with a two-way trust relationship between them, and I
would like to add a user from Domain A to one of the groups in Domain B.
Unfortunately, all I can seem to do is only add users from Domain A to one
of the Built-in groups of Domain B, not to any of the groups in the Users
container.

Is this at all possible?


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