Moving from 32 to 64 bit builds on Solaris

I've got an install of Postgres 8.2.3 on a Sun box that's ticking
over nicely -- I'm pretty happy with it and how it's performing. It's
a 32 bit build, and the machine I'm running it on has a lot of extra
memory.

I assume I'll have to do a 64 bit build to use more than a few gig of
shared buffers. If I do that, though, am I going to have to do a
database dump and reload, or will the disk files be compatible and it
just a matter of shutting down the 32 bit server and firing up the 64
bit one?
--
                Dan

--------------------------------------it's like this-------------------
Dan Sugalski                          even samurai
dan@sidhe.org                         have teddy bears and even
                                       teddy bears get drunk