[Samba] Samba authentication slow against PDC

[Chris Snider]

We are currently running three Samba 3.0.x file servers which authenticate
against a Samba PDC running LDAP.  2 out of the 3 samba servers authenticate
quickly(<5 seconds) when using smbclient -L localhost -U username however
the third will eventually time out saying "Server did not respond in 20000
milliseconds.  NetBIOS over TCP disabled" when there is any sort of load on
it ~30% cpu usage.  If there is no load on the server then authentication
still takes around 15 seconds using the smbclient command.  When the server
is under a load domain computers are unable to map drives when running their
login script although once authenticated they can browse and map drives
without issue.  The only way to fix the problem is to reboot the server
several times until all users get their drives mapped then everything is
fine.   The box in question is running Fedora core 2 with all patches
applied using yum.  If you need my configuration or any other information
please let me know. 

Thanks,
Chris