[Samba] tdbsam - can't connect if the password is 16 characters long

[initiators at free.fr]

Hello

I've set up a Samba server as a PDC using a tdbsam backend.

I first tried to access the shares with the usernames/passwords of the
domain users I created, everything was OK (well almost, I'll post
another one on this).

Then I tried to join the domain with a PC and had errors "account not
found", or something like that. This was on Windows XP SP2.
I tried to mount a access a share as root but it wouldn't connect, as if
the password wasn't good. I tried this on Windows XP SP2, Windows 2000
SP4, and Windows NT4 SP6.
Then I did a "pdbedit -Lw" to see what the password hashes looked like
and noticed than root had 32 X characters in the LANMAN hash, meaning
account disabled according to man.
I tried "smbpasswd -e root" with no effect.
Then I tried to change the password from 16 characters long to 8
characters long and it worked.

I've for now just moved two PC to the new domain, if I do a "pdbedit
-Lw" I see 32 X in their LANMAN hashes and no problem so far.

Is there a limitation in the length of the password ? Where does this
problem comes from ?

Thanks in advance