ppp refusing connections due to pam

[Lindsay Allen <allen@cleo.murdoch.edu.au>]

Hi,

I used apt yesterday to upgrade some packages including some libpam
packages and now an incoming ppp connection fails with entries like this
in the log: 

Oct  1 21:17:08 elm PAM_unix[25488]: check pass; user unknown
Oct  1 21:17:08 elm PAM_unix[25488]: authentication failure; LOGIN(uid=0)
-> CONNECT 57600 for login service
Oct  1 21:17:10 elm login[25488]: FAILED LOGIN 1 FROM  FOR CONNECT 57600,
Authentication service cannot retrieve authentication info.

Connections worked yesterday morning.  I use mgetty with this line:

/AutoPPP/ -     au_ppp  /usr/sbin/pppd debug


My box is potato with some slink packages still installed.  

elm:# dpkg -l login libc6 libpam\* ppp\*
ii  login           19990827-4  System login tools
ii  libc6           2.1.2-2     GNU C Library: Shared libraries
ii  libpam-modules  0.69-7      Pluggable Authentication Modules for PAM
ii  libpam-runtime  0.69-7      Runtime support for the PAM library
ii  libpam0g        0.69-7      Pluggable Authentication Modules library
ii  ppp             2.3.9-1     Point-to-Point Protocol (PPP) daemon.
pn  ppp-pam         <none>         (no description available)

I have no idea at all what PAM_unix is or how to go about fixing this
problem.  I would just like to ppp working again which will buy me time 
to research all this properly.  Any help would be most appreciated. 

Thanks,
Lindsay
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Lindsay Allen   <allen@cleo.murdoch.edu.au>  Perth, Western Australia
voice +61 8 9316 2486    32.0125S 115.8445E              Debian Linux
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