Client frequent disconnection + strange logs

[François Désarménien]

Hello,

Although I've been using samba for years at my customers
office, I recently moved one on a HP E60 server running
RedHat 6.2.

The samba version is 2.0.6, untouched from the distribution.

They use a (weird) accounting software built on the top of
FoxPro, requiring a *huge* amount of open files. I accordingly
raised the values for files-nr and inode-nr and the stats seem
ok.

They have many times a day failure from their software, telling
them it cannot open a file (random name) on the file server.

So I set debug level to 3, to try to see what's going on and told
them to phone immediatly and stop working as soon as the symptom
shows again.

I then wandered through the logs and found thing that seem strange
to me:

in the log.machine, I find at the same timestamp close requests,
followed by two line of the form:

[timestamp]lib/doscalls.c:dos_ChDir(336) dos_ChDir to /var/sauvegarde
[timestamp]connexion closed for user compta

and then a reconnection to the same user, at the same timestamp.

I don't understand the reason of the deconnection, and the dos_ChDir
call, as neitheir the client nor samba knows anything about the
/var/sauvegarde directory, which I use to store backup locks.

Beside this, at the very same time, I find in /var/message the line

[timestamp]PAM_pwdb: (login) authentication failure; (uid 0) -> compta for samba service

which I cannot neither explain.

The client is a Windows 98, with registry patched to allow plain text
passwords (closed private network), and smb.conf  is not set to allow
crypted passwords.

Does any of you, gurus, could tell me what's going wrong, or in which
direction should I continue searching to get more interesting stuff ?

I thank you for your time and help,

François Désarménien

PS: could you please CC to me, as I'm not (currently) signed up on the list ?