samba - Feb 2007 - Win2K Lockdown: The master browser has received a server announcment...

I'm seeing errors like this in my event viewer on win2k clients:
Source MRx Smb
"The master browser has received a server announcement that 
computer CONAN that believes it is the master browser for the 
domain ...

The master brower is stoppong or an election is being forced."

Event ID 8003

The other error that frequently occurs with this:
Source: Netlogon
"No Windows NT or Windows Active Domain Controller is available 
for the domain SJSA.  The following error occured:
The RPC server is unavailable.

Event ID 5719


Setup:
Server Samba 2.2.8a
Clients Win2K SP4
lmhosts file with name of PDC with #PRE #DOM:SJSA in it.

Kerio Sunbelt personal firewall with rules to
1.  Allow all traffic between client and servers.
2.  Block all traffic between clients
3.  Block all traffic to/from broadcast address.

DHCP server is set to tell clients

option netbios-name-servers 192.168.1.241 ;
option netbios-node-type 2 ;

Conan is the master browser and wins server.

The system mostly works, except intermittently won't load 
profile, or takes a long time to load profiles.

(As a side effect to trying to stomp client to client 
communications logins, when they work are very fast.)

Ideas?