Sorry, I misunderstood, I thought you meant the big kid database product DB2 as opposed to a server or database name.
Let's clarify our technical terms here:
When you select Database->Set Location where does it display DB2?
There should be:
Server Type
Server Name
Database
User ID
Under the Server Type will be ODBC or whatever
Server Name will be the name of the SQL Server database
Database will be the Database name on that server
User ID will be the logon being used
There shouldn't be anything called data source.
Perhaps you mean the DSN because you're using ODBC, which doesn't matter, you can name any connection in ODBC whatever you'd like (except reserved names).
Remember, when you tell people that you're pointing to DB2, they're probably going to think that you mean the big boy database product, not a server. It's like saying that you have a server named Oracle...
-k