DATA directory on network attached storage

We are currently considering the possibility of creating a warm standby
machine utilizing heartbeat and a network attached storage device for the DATA
directory.  The idea being that the warm standby machine has its postmaster
stopped.  When heartbeat detects the death of the master server, the
postmaster is started up on the warm standby using the shared DATA directory.
Other than the obvious problems of both postmasters inadvertently attempting
access at the same time, I'm curious to know if anyone has tried any similar
setups and what the experiences have been.  Specifically is the performance of
gigE good enough to allow postgres to perform under load with an NFS mounted
DATA dir?  Are there other problems I haven't thought about?  Any input would
be greatly appreciated.

Thanks!

--
Jeff Frost, Owner     <jeff@frostconsultingllc.com>
Frost Consulting, LLC     http://www.frostconsultingllc.com/
Phone: 650-780-7908    FAX: 650-649-1954