UNIX password snyc doesn't work

[T.Zwinge at Alexius.de]

I can't get the UNIX password sync to work.
The UNIX password simply isn't changed when I change the SMB password.
I'm using the following settings:

security = DOMAIN 
password server = NT-PDC NT-BDC
smb passwd file = /etc/smbpasswd 
passwd program = /usr/bin/passwd %u 
passwd chat = *new*password* %n\n *new*password* %n\n *changed* 
passwd chat debug = No 
unix password sync = Yes

I'm using Samba 2.07 on a SuSE Linux 7.0 PC.

Thanks,

Tamo