I have a simple VFP app. I would like to put all my rules in the DBC so clients who buy the app can add onto its functionality through ODBC. My problem is as soon as I place a rule in the stored procedures that is slightly complicated ( see below ) and access the data via VFP ODBC driver, the rule fails - always - even if the entered data is correct. If I use a simple rule it works. For example, this works:

PROCEDURE AddressRules
IF EMPTY( AddrID )
RETURN .F.
ENDIF

but, this does not work:

PROCEDURE AddressRules
USE Person IN 0 AGAIN ALIAS AddressRules
IF NOT SEEK( PersonID,"AddressRules","I1" )
USE IN "AddressRules"
RETURN .F.
ENDIF
USE IN "AddressRules"

Are some commands and functions not supported if accessed via ODBC? If yes, where can I find a detailed list?

Thanks for any help.
Ben