[Samba] Samba WINS Server losing all elections against

[ZeWaren / Erwan Martin]

Hello everybody.
I've been trying for weeks to find a solution for my problem, but since 
I couldn't find anything, here I am.

I manage a network of about 200 PCs, 90% windows XP and Vista, 10% linux.
A samba server is located on the main server, acting as a WINS server, 
to manage the list of connected computers.

However, when a resident computer is badly configured (ie no wins server 
is specified), or if a stupid firewall is installed on it, that machine 
tries to become the local master. So it starts an election with my samba 
server... and it wins. This is the part I don't understand. Why is my 
WINS server always losing elections against other computers? I set its 
os level to 255, which I read is the highest value.

Here is my smb.conf:
[global]
  netbios-name = myworkgroup-server
  workgroup = MYWORKGROUP
  server string = myworkgroup Server
 
  wins support = yes

  prefered master = yes
  local master = yes
  domain master = yes
  os level = 255

Well, if I configure the resident computer correctly, ie:
-On windows computers, add a 'wins server' in the TCP/IP properties, and 
set the registry parameter 
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Browser\Parameters\"MaintainServerList" 
to No
-On linux computers, set 'os level' to 0 and 'local master' to no in the 
samba configuration file.
Then no election is generated and so my server is fine.

Here is an example of what I see in my log file when I'm losing my 
status of 'local master'

[2008/09/30 19:31:01,  0] 
nmbd/nmbd_incomingdgrams.c:process_local_master_announce(308)
  process_local_master_announce: Server PC-DE-CRETIN at IP 192.168.xx.yy 
is announcing itself as a local master browser for workgroup MYWORKGROUP 
and we think we are master. Forcing election.
[2008/09/30 19:31:01,  0] 
nmbd/nmbd_become_lmb.c:unbecome_local_master_success(148)
  *****

  Samba name server MYWORKGROUP-SERVER has stopped being a local master 
browser for workgroup MYWORKGROUP on subnet 192.168.1.2

  *****
[2008/09/30 19:31:18,  0] 
nmbd/nmbd_become_lmb.c:become_local_master_stage2(395)
  *****

  Samba name server MYWORKGROUP-SERVER is now a local master browser for 
workgroup MYWORKGROUP on subnet 192.168.1.2

  *****

I also don't understand why the log file says I became local master 
again after losing that status, since it's not anymore (Querying the 
server does not work).
The only way I've got to get it work again is to force-reload the samba 
server (/etc/init.d/samba force-reload).

Does anyone know what I should do to get my WINS server to win the 
elections? I'm tired of having to restart my samba server every 20 
minutes to make sure my people get a working list of computers.

Thanks in advance.
Erwan Martin, French network administrator student.