Assigning from within Curriculum Library

This is probably more of a Class Server question - but have posted here
as well in case anyone can help.

I am running Class Server 4.0 and Sharepoint Portal Server 2003.

If I open the Curriculum Library (in Sharepoint portal) to assign a
Learning Resource to a class, the link cannot find CSUI\AssignLR.aspx,
even though that file is present on that folder.

Any ideas?

Mark

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