>This comment from the blog mentioned in another reply sounds like exactly your issue, but no resolution proposed:
>==============================================================================
>The same issue came up only when we upgrade the db to SQL Server 2005 for 2000, while the middle tier is always using .NET 2.0.
>
>As an example, one of the problematic sproc uspGetOrderItem is like:
>
>Select o.orderid, i.ItemName, i.Qty
>
>From order o join orderitem i on o.orderid = i.orderid.
>
>I replaced o.orderid in the select list with i.orderid. NO other code change at middle tier, and it worked! I feel lucky, but I cannot think of any reason why it worked on SQL Server 2000 but not on SQL Server 2005.
>
>Can someone help?
>==================================================
>And reading other comments it looks like it's not really a serious issue and perhaps can be simply ignored (of course, if none of the proposed solutions will work).

Yes, I thought about that as well. Because it doesn't like the master primary key to appear more than once, I thought about using the foreign key instead in the SQL result.