smbmount'ed fs "dies" after a short time

[Jim Garrison]

I have a linux (RH6) client that smbmounts a filesystem
from an NT server.  After some short unspecified period
of time, all attempts to access the mounted filesystem
on the linux box result in "Input/Output Error".
I can't even smbumount the file system (same error
message).  The NT system continues to function, and
other MS clients (Win95 and NT) do not have any problems
with the filesystem (i.e. everything else continues working
normally).  Samba version according to RPM is samba-2.0.5a-1. 

Interestingly, rebooting the linux system DOES NOT solve
the problem.  Any attempt to reference the mount point,
even after the reboot, gets the same "Input/Output" error.

To correct the problem I have to do the following on the
linux box:

1) shutdown to single-user mode
2) rmdir the mount point
3) reboot

Can anyone help me get smbmount-mounted file systems
to be more stable?

TIA,
Jim Garrison
jhg at acm.org