Win2k3 SP1 and Win95 clients

I have a new Win2k3 server install with a number of Win2k pro clients plus a
few Win95 and Win98 cients. I installed SP1 on the server early in the
setup. None of the Win95 clients have been able to browse server shares or
join the domain. The Win2k and Win98 clients browse shares and join the
domain OK.

I've googled the topic, found a number of posts relating to this symptom and
tried their recommendations. I've installed dsclient on one of the win95
clients but no change. I set the LMCompatability reg key as recommended on
the client (value 3, also tried 1) but no change. I've disabled the Win2k3
server MS Network Server "always sign" policy but no change.

I deinstalled SP1 from the server and the Win95 clients (both with and
without dsclient) are now able to browse shares and join the domain.

I've not been able to find any pointers on why SP1 in itself would be
affecting authentication of just the Win95 clients. Does anyone here have
any similar experience ?

Thanks,

Dave Green