[Zope] Postgres and transactions

I'm attempting to use a ZSQL method to create a new user in a postgresql database (in the CREATE USER... sense), using Popy and postgres 7.0. The problem is that CREATE USER throws an error if you use it inside an explicit transaction. So: Does any know how to explicity turn off transactions for a particular ZSQL method? Do any of the other postgresql adapters work any better? (I'd test them, but I've had build troubles with the others.) Can I get away with just inserting the appropriate data into pg_user or is CREATE USER doing some other magic? I'd be grateful for any clues anyone has. John