>To my knowledge, REPLACE performs a lock by default.
>If you remove the RLOCK() does the REPLACE work properly?
>I would try to use the RLOCK() as a test to see if the record
>is available, remove the lock, and do the REPLACE.

Good grief, no! There's plenty of time between an UNLOCK and the next statement for
another user to get in there and change the data. The lock should stay in effect
through the replace.