Thanks for the responses!! 

After spending all day on this....I know more about the problem which I think revolves around the 32-bit/64-bit issue.

I'm using...

I am having a similar problem - SSIS package executes fine in BIDS but fails when scheduled as SQL Server Agent job. Different error...

Windows Server 2003/SQL Server 2005 64-bit.

Package Protection...

I understand what you’re saying regarding data caching.  I still think it odd that this dramatic of a result occurs with the processes running simultaneously!!

Actually all three procs access the same three large tables, albeit with different data ranges, groupings and selection criteria.  This to simulate our routine environment...

Sorry I don't have any answers for you - just a similar question.  Migrating from 32-bit SQL Server 2000 to 64-bit SQL Server 2005/64-bit Windows Server and need Oracle connectivity...