[linux-cifs-client] no read permission on a cifs share

[Salvatore Filippone]

Hello, 
It seems that this is a problem cropping up every now and then, however
I could not get it to work. 
Scenario: I have a Windows 98 machine (a bunch of them, actually) which
I want to move behind a Centos 5.2 firewall, and I would like to mount
their shares, rsync them onto the firewall disks, then export these
directories to (some selected clients) on the external network. 
Problem is, after finding out the servern= and sec=lanman options to
mount.cifs  and so finally being able to mount, I stumbled on the
permission denied while trying to copy (actually, rsyncing) the mounted
files. I get
file XXX
XXX:  writable, executable, regular file, no read permission

Is there any place where I can find info on how to proceed? 
Even finding the servern and sec options was non-trivial, the
combination that works (seemingly) is not documented.... 

Is anybody willing to give a hand, and/or what sort of debug details
would be needed? 

Thanks a lot in advance

-- 
Salvatore Filippone <salvatore.filippone at uniroma2.it>