checkpassword and shadow password

Hello guys,

I have set on Debian shadow passwords and I installed qmail on it.
Problem appeared when I set pop3d server. I could not autentificate
user. I patched checkpassword 0.81 for shadow passwords. I got some
recommendation from Inet to change file /etc/pam.d/passwd like this:



# beginning of the file
auth       required   /lib/security/pam_pwdb.so shadow nullok
account    required   /lib/security/pam_pwdb.so
password   required   /lib/security/pam_cracklib.so retry=3
password   required   /lib/security/pam_pwdb.so use_auth_ok nullok
shadow
#
#
# next line was uncomented in file before changes were applied 
#password   required   pam_unix.so nullok obscure min=4 max=8 md5
#
#
# end of the file


After these changed I found I can not create ordinary user with adduser
command and with linuxconf as well, but I could do pop3 connection and
autentification of pop3 user. When I put file /etc/pam.d/passwd back I
could addusers but not autentificate pop3 users again. Do you know how
can I set shadow passwords with qmail-pop3d server right?

Thanks 

Petr