Using the kernel 2.6 Kamikaze 7.06 image on my WRTSL54GS, nfsd refuses to load.
The error messages from dmesg are:
nfsd: Unknown symbol find_exported_dentry
nfsd: Unknown symbol export_op_default
I believe that there should be a module called exportfs.ko, but it does not exist.
From googling around a bit, I read somewhere that nfsd compiled as a module may have trouble with exportfs compiled into the kernel rather than as a module.