depends on which version
Hi Mary Anne
There's some very materialistic schools of Buddhist thought which basically utterly deny any positive content to Nirvana as a state of mind. They just see all striving as pointless and worth abandoning - ceasation is enough.
OTOH there are theistic Buddhists who make the philosophical point that there can be no Refuge and no Dharma without an Eternal, Timeless Someone.
Where Buddha stood on the issue is anyone's guess.
Adam