I don't understand why you'd need to join two MDX queries together. In the above example wouldn't you just have a set with the multiple dates you want to select.

Like

SELECT NON EMPTY { [Measures].[Quantity Received] } ON COLUMNS,

non empty {[Customer - ID].[Customer - ID].[All].Children}

* {[Entry Date Time].[01/01/2008],[Entry Date Time].[01/02/2008]} ON ROWS

FROM [Sales]

Am I missing something?

Mack