samba - Sep 2012 - Samba 3.5.15 disconnections with MAC OS clients

Hi All

I am connecting about 5 Mac 10.7/10.8 clients to a Samba 3.5.15 server. The Mac
clients are running normal MS Office applications. I see that (very often) the
clients run into problems trying to save documents (especially Excel) to the
exported Samba Share. Sometimes I cannot connect to the Samba server and have to
explicitly reconnect via the finder.

All my clients are members of a Windows AD domain (Win2k3SP2). There are about
200 users configured. I have also connected the Samba server to the AD domain.

Here is the interesting part. The problem only occurs on Mac clients that are
members of the domain. Also if I leave the domain from any of the Mac clients, I
am able to save the documents without any problems.

Has anybody seen this behavior? Please let us
 know.

Thanks in advance
Ridgetree