disable "fake" samba authentication error messages

[Urs Rau]

What bothers me is that samba is filling up my log files with a lot of 
extraneous/fake entries about authentication failures. "Extraneous/fake" - 
because all it is is a reflection of the way the protocol actually tries to login - 
going through the upper/lower case mutations as configured.

sample log entries: 
-----------------------
Jun 30 19:40:35 dolphin PAM_pwdb[26988]: 1 authentication failure; (uid=0) -
> root for samba service
Jun 30 19:40:36 dolphin last message repeated 4 times
-------------------------------- 

Is there any way to have samba only log the really failed logins? (i.e. only if 
the password actually never matched - in any of these mutations that are 
automatically tried on a single connect)

I really do want to use PAM - because of it's otherwise tight and nice integration
with the operating system.

What and where can I change this behaviour? 

BTW I am running samba-1.9.17p4 on Redhat 4.2, but I don't think the 
problem has changed even in 1.9.18p8 (at least not according to a colleague 
that I checked with)