r12682: This patch finally fixes our kpasswdd implementation to be compatible

r12682: This patch finally fixes our kpasswdd implementation to be compatible
with clients compiled against the MIT Kerberos implementation.  (Which
checks for address in KRB-PRIV packets, hence my comments on socket
functions earlier today).

It also fixes the 'set password' operation to behave correctly (it was
previously a no-op).

This allows Samba3 to join Samba4.  Some winbindd operations even work,
which I think is a good step forward.  There is naturally a lot of work
to do, but I wanted at least the very basics of Samba3 domain membership
to be available for the tech preview.

Andrew Bartlett