windows98 logon problem

I have 15 win89 machine in my network controlled by
windowsNT PDC and BDC and a win2000 active directory
service created trust relationship with PDC/BDC.But the
problem is when I create a new user account on pbd or bdc
it is creating and showing on both pdc and bdc. But when I
try to login from any win98 machine it is showing an
error 'user not found'. even though it is still loging in
with old user account and administrator. some time when I
re-boot machine 1/2 time it is logging in with new account
and some time it is showing the error 'user not found'. i
could not find figur it out what may be the problem. will
you please give me any tip to solve the problem.