Dialup passwords in System 5

[Theodore Hope]

Does anyone know anything about the dialup password mechanism available
under System 5?  According to the source for 'login,' the files '/etc/dialups'
and '/etc/d_passwd' are checked for dialup access and the user is prompted
for an additional password if necessary.  I have not been able to find info
about this stuff anywhere (no, it's not in man4) and would appreciate further
help.  To all you AT&T folks:  How about getting your documentation together?

		Thanks in advance,
-- 
Theodore Hope
School of Information & Computer Science, Georgia Tech, Atlanta GA 30332
CSNet:	Hope @ GATech		ARPA:	Hope%GATech.CSNet @ CSNet-Relay.ARPA
uucp:	...!{akgua,allegra,amd,hplabs,ihnp4,seismo,ut-sally}!gatech!hope