We have a NT4.0 tacacs+ ACS server that we want to turn off, permitting connections with blank usernames and passwords (or fictious). Our clients actually connect to us via PPP/ISDN with a username/password pair, in chap. Is it possible to disable ppp chap processing from our IOS 12.2 3600, forcing an always-true auth? The command "aaa authentication ppp default none" permits Windows RAS users to authenticate with every username/password, but Cisco users cannot complete the PPP LCP phase.