[Samba] "permission denied" problem between Samba 2.2.3a and Mentor Graph ics database

[Statts, Pearce (IndSys, GEFanuc, NA)]

Admins,

We have a clustered fileserver running SunOS 5.6 and Samba 2.2.3a.  The
fileserver hosts a large number of CAD designs for the engineering teams we
have working here.  Two weeks ago, we upgraded Samba from 2.0.4 to 2.2.3a,
and now one of our engineers is reporting a problem with accessing one of
his Mentor Graphics databases.  When he attempts to open the design database
from his Win NT machine, he gets the following error:

				//  Error: $open_file returned error status
at line 3545 of file
E:/MentorGraphics/MGC_HOME/pkgs/layout/userware/En_na/lay_area.ample within
function $prepare_re_area (from: Uims/Ample/Ample_eval 1D)
				//  Error: Unable to open file
j:/cdi/cpu/sbcp3/ccp3/pcb/RE/Pcb/ccp3.pcb (from: Uims/Ample/Ample_stream 01)
				//  Error: Permission denied (from: Unix
000D)

Note the very last line of the error message.  Before Samba was upgraded to
2.2.3a, the user was able to access all of his files without a problem.
I've done some investigating, and changed the permissions on the file in
question from rwxrw-r-- to rwxrwxr-x, hoping that this would allow the
Mentor Graphics program to correctly access the file.  It failed, and when I
logged back onto the Sun box, I saw that the permissions on the file had
reverted back to rwxrw-r--.  Mentor does not officially support Samba, and
I'm thinking that this has something to do with the problem.  Here is what
they have to say about it:

TechNote Id:	20996
Topic:		OS/Networking
Product:	Design Capture
Versions:	n/a through n/a
Creation date:	03/22/2001
Modified date:	01/03/2002
Short Desc:	Unable to save file on a remote filesystem

Problem Text:	You are unable to edit certain files (for example, the Net
Properties file) when
the file is on a remote file system. When you attempt to save the file, the
tool
gives a permissions error, even though the permissions are wide open.
What's wrong?
Solution Text:	VB software releases (through 2000.0a) rely on Windows file
locking,
and are therefore not supported on filesystems that do not support Windows
file locking.  The only  supported filesystems are as follows:

*   Win95-Fat16
*   Win98-Fat 16 or Fat32
*   Windows NT-Fat 16 or NTFS
*   Windows 2000-Fat16, Fat 32, or NTFS
*   Novell 5.X NWFS (Netware File System),  NSS (Novell Storage Service)

No other flavors or implementations of remote file servers are supported.
The list of
unsupported remote file servers would include, but is not limited to:

*   UNIX (including LINUX) native file systems
*   NFS (on UNIX or PC)
*   Samba
*   Network Appliance / Auspex file servers
*   Novell Netware prior to Netware 5.0

Two points here.  Mentor's tech note states that their products are "not
supported on filesystems that do not support Windows file locking", and they
include Samba in their list.  Is that right?  I could've sworn that Samba
DID fully support and cooperate with Windows file locking.  Now, although
Mentor does not "officially" support Samba, it was working FINE on Samba
2.0.4, and the only change we've made is to upgrade to 2.2.3a.  No changes
have been made to smb.conf at all.  My theory is that there is a file
locking option in Samba that isn't set correctly.  Does anyone have any idea
what could be the problem?

Thanks,

Pearce Statts
GE Fanuc Automation IT
pearce.statts at gefanuc.com