Samba and NT4+SP5

Hello, we have two Samba servers running on an LAN for some months. One is on RedHat 6.0 (samba 2.0.3) and the other on Solaris 2.5 (samba 2.0.5).

All the Windows boxes connect to them with “clear text” passwords. No problems until we installed Service Pack 5 on two fresh NT 4.0 machines.

Right after installation the NT boxes can see the servers in Network Neighbourghood. As soon as we add SP5 to the mix they disapear and not even with “Start | Find | Computer” it is possible to find locate them. The same results with SP4…

Has anyone experienced this problem? What is the cure or workaround. Should I try SP6 or SP6a?