samba - Nov 2008 - INVALID PIPE HANDLE when join machine to domain

When I try to join Windows machine to my domain I get this error in log
file:
[2008/11/07 17:09:18,  1] smbd/ipc.c:api_fd_reply(333)
  api_fd_reply: INVALID PIPE HANDLE: 76c7

2 processes remain to hang until I kill them:
root     10093  0.0  0.0   4020   588 ?        S    Nov07   0:00 sh -c
/usr/sbin/smbldap\-useradd \-w "ibank2\$"
root     10094  0.0  1.3  59368 13964 ?        S    Nov07   0:00
/usr/bin/perl -w /usr/sbin/smbldap-useradd -w ibank2$

If I run smbldap-useradd -w "machinename" by hand it works properly.

Samba is configured as domain controller and in smb.conf I have this string:
add machine script = /usr/sbin/smbldap-useradd -w "%u"

samba version: 3.2.3
smbldap-tools: 0.9.4
Ubuntu 8.10 (all packages from ubuntu repositoies).