Derived attributes in a dimension

SQL 2005 SSAS - is it possible to create a derived attribute in a Dimension or does it have to be done in the underlying table.

Specifically, I have a geographic location Dimension where the top level is "Area" (USGulf, USWestCoast, Caribbean etc). Now there is one part of the company that likes to group these together into Zones. I can see how to do this in SQL in the underlying table or in reports in SSRS, but ideally would like to do this in the cube.

Thanks

You could add a Named Calculation for Zone to the dimension table in the Data Source View. This would be a SQL expression - the underlying table structure wouldn't change.