[Samba] plaintext backend

[Karel Kulhavy]

Hello

I would like to use plaintext backend with a simple Samba 3.0.6
configuration to get rid of the system of double passwords and rely just
on the plain old unix /etc/passwd ones.

However I couldn't find any information about it in
1) man smb.conf
2) online Samba official HOWTO

I tried putting passdb backend = plaintext into a smb.conf file with
security=share and the Samba server doesn't seem to work at all:
root at oberon:~# smbclient -L oberon 
protocol negotiation failed


However when the line passdb backend = plaintext is commented out, the
smbclient -L oberon normally runs - prints out the shares.

I have tried to put passdb backend = fuck into the config file and
testparm said the smb.conf if OK (!!!). So the I can't even determine
what should be put into smb.conf to get plaintext passdb backend:
1) the official HOWTO lacks this info
2) manpage lacks this info
3) testparm is broken

Please tell me what should be put into passdb backend to get a
security=share server and plaintext passdb backend.

Thanks,

Cl<