mount_smbfs: RPC struct is bad

[Sheldon Hearn]

Hi folks,

I'm using SMBFS on FreeBSD 4.9-PRERELEASE from 2003-09-18, and running
into problems mounting W2K shares.  I was last able to mount these
shares a month ago.  Since then, the only change I'm aware of was the
world update (to catch security patches) and accompanying mergemaster.

Here's the config:

/etc/fstab:
//backup at foo/backup /smb/foo smbfs noauto,ro,-N 0 0

/etc/nsmb.conf
[default]
workgroup=BAR
[FOO:BACKUP:BACKUP]
password=xyzzy

Here's the problem:

# mount /smb/foo
smbfs: unable to open connection: syserr = RPC struct is bad

Any ideas?  Google, Rambler and a search of the freebsd-questions
archive both came up empty-handed.

Ciao,
Sheldon.