freeze on logout/shutdown (PR#664)

[Andrew Tridgell]

> we've got samba-1.9.17p2, FreeBSD 2.2-STABLE (last cvsup 6 Oct 1997) and
> 15 workstations under Win95 (rus), Win95 OSR2 (rus) configured to make
> domain logons to samba server (and to save user.dat etc. on network)
> the problem is: win95 stations cannot shutdown, reboot or 'login
> as different user' when the user is logged on from two or more
> workstations. 
> people reported the same problem under Solaris 2.5.1x86 and Linux

I've just fixed this bug. It was a problem in the WACK code (wait for 
acknowledgement) in nmbd. These get produced when two machines try to
register the same name on the network. It could also happen if one
machine shutdown suddenly then the same user logged in again on
another machine.

It will be fixed in the next release. Unfortunately I didn't find the fix
in time for the 1.9.17p3 release.

Andrew