Spurious client disconnects with MAC OSX 10.7/8 and AD

[shani wijaya]

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