If one attempts to mount a directory from an FC5 NFS server using certain NFS
parameters, then the kernel panics.
For example, configuring the automounter on a Solaris 8 sparc machine to mount
my home directory (on an FC5 i386 machine) with the NFS parameters:
then the FC5 box panics its kernel.
I think we needed these parameters for an earlier version of Fedora.
If one removes the NFS parameters, the FC5 box is OK. But life is now interesting
because one has to remember which servers have been updated - if you pick one
that hasn't been, it's reboot time on the FC5 box.