The vendor may be using index hints.  If this is the case, then any query referencing that index will fail.

Using OPENQUERY will first return all the data from Oracle to SQL Server.  What you could try doing, if you are running 2000, is create a user defined function.  Inside...

I have done this with an Access 97 password protected database from SQL 2000 before.  You should be able to plug in your db location in the data source box,...