added nullDevPtr to Driver API
added nullDevPtr to Driver API

Ignore-this: 189a37a7feb6bc81462d75feffc40121

darcs-hash:20100212042424-879de-eb204d44749e5f29225464b0a30091ac7f29dc97.gz

phaazon/cuda,phaazon/cuda,mwu-tow/cuda,phaazon/cuda