samba and Windows NT Ws 4.0 SP6

[Arianto C Nugroho]

hi ...
i've been trying to make a pdc using samba 2.2.1a in my lab which have 2 kind
of NT workstation, one with SP4 the other with SP6. when i try to login to my
SP6 clients, i got kick out right after i login without any error/messages from
windows. but the same setting works fine with my SP clients. 
can anyone tell me how to fix this without having to downgrade to SP4 ??

thanks