Samba 1.9.18p1: Cannot browse DMB server any more

[Ole Holm Nielsen]

After upgrading to Samba 1.9.18 (and later 1.9.18p1) we have a browsing
problem:  Win-95 PCs on remote subnets cannot browse the Domain
Master Browser (DMB) any more.  The problem goes away when running
Samba 1.9.17p4 on the DMB, using the same smb.conf.  This points 
to a new bug in 1.9.18.

A simple drawing of the network topology:

     Router ================= Router 
        |                       |
   DMB--|                       |--PC(B)
        |                       |
 PC(A)--|                       |--Samba C(1.9.18p1)
        |--Samba E(1.9.18p1)

Observations:

1. PC(A) on the DMB's own subnet can browse the 1.9.18p1 DMB just fine, 
but PC(B) (that had no problems with 1.9.17 servers) on a remote 
subnet cannot browse the contents of the DMB.
2. PC(B) on the remote subnet can browse a local 1.9.18p1 (Samba C)
server 
on the same subnet just fine, as well as other (Samba E) servers on the 
DMB's subnet.  
3. When you click on the DMB in the PC(B)'s Network Neighborhood, 
it says "Network error"; a longer error message is seen in a 
DOS box when you do "net view \\DMB".
4. On a remote-subnet (Samba C) server "smbclient -L DMB" shows
the DMB, so the problem seems to be restricted to Win-95 clients.
5. There are no error messages in the DMB's nmbd logfile that 
obviously point to a problem.
6. Replacing the 1.9.18p1 nmbd by a 1.9.17p4 nmbd on the DMB cures the 
problem, but this is hardly a long-term solution :-)

Conclusion:  There is a problem when a Samba 1.9.18p1 server is also a 
Domain Master Browser.  Remote-subnet Win-95 clients cannot browse
the DMB any more.

Our DMB's smb.conf file can be seen as http://info.fysik.dtu.dk/smb.conf
if anyone is interested.  The DMB's OS is IBM AIX 4.2.1.

Has similar behavior been seen elsewhere, and how about a resolution
of the problem ?

With best regards,

Ole H. Nielsen
Department of Physics, Building 307
Technical University of Denmark, DK-2800 Lyngby, Denmark