How to add security on dial up lines?

[Bjorn Engsig]

When connecting a modem to an RS6000 (AIX 3.1 9030), is there a way to
either:

- Have login on this line prompt for an extra dialup password (like the
  undocumented /etc/d_passwd in System V).

- Only allow certain login id's on this line?

Thanks for any help,
-- 
Bjorn Engsig,	Domain:		bengsig at oracle.nl, bengsig at oracle.com
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