NCP: Mount lost

Hi,

there is a SLES10SP2 (with all patches) with an NCPmount of a volume from a
NW-Server.

Some times the SLES lose the mount.

:ls /mnt/ncp/VOL1

gets an I/O Error.

I can do a 'mount -t ncp -a' and the mount is back. But a:
:mount

shows then two (or three, four, ...) mounts of the same Volume to the same
place!?!?!

What's the way to get a stable connection between SLES and Netware-Volume?

TiA

Bernd