>AFAIK there has been no changes between VFP 5 and 6.

That's really not the case when manipulating the DBC; you have to be extremely careful not to modify the DBC, especially RI, triggers and SPs using VFP6 if you have a continuing need to use the DBC under VFP5; there are issues with the embedded p-code incorporated into the DBC content attempting to fire things from VFP 5 if the DBC is compiled under VFP 6, even if you do not use any of the features added under VFP 6.