I'm pretty positive from my recent viewing of the disc that it is sub-titled from the Japanese and that there is not a dubbing option. Actually, the movie hardly needs dialogue at all, as it relies so heavily on atmosphere and visuals.
On the version we rent at Hollywood Video (which I believe is a region-free version, I've also seen it for sale at Best Buy) you can watch with subtitles or with a bad, very bad, horribly bad, annoyingly sucky English dub.
UK is about to get a nice Special Edition release from Premier Asia. I wonder if it's worth buying yet another edition of this somewhat excellent movie?