chap auth over frame relay

[jennytan <jennytan@xxxxxxxxxxxxxxxxx>]

R2 and R4 are connected via Frame Relay.  It worked when I didn't have
authentication turned on. I saw authentication error as soon as I turned on
ppp auth. Please see the detail below.  Any idea what's wrong?

On R4:-
username R4 password 0 ipexpert
interface Serial0/0/0
 no ip address
 encapsulation frame-relay
 no fair-queue
 frame-relay interface-dlci 402 ppp Virtual-Template1
 no frame-relay inverse-arp

interface Virtual-Template1
 ip address 150.50.24.4 255.255.255.0
 ppp authentication chap

R4#
*Feb 18 22:50: 35.906: Vi1 PPP: Authorization required
*Feb 18 22:50:37.922: Vi1 CHAP: O CHALLENGE id 47 len 23 from "R4"
*Feb 18 22:50:37.922: Vi1 CHAP: I CHALLENGE id 129 len 23 from "R2"
*Feb 18 22:50:37.922 : Vi1 CHAP: Unable to authenticate for peer
*Feb 18 22:50:39.938: Vi1 PPP: Authorization required
*Feb 18 22:50:41.954: Vi1 CHAP: O CHALLENGE id 48 len 23 from "R4"
*Feb 18 22:50:41.954: Vi1 CHAP: I CHALLENGE id 130 len 23 from "R2"
*Feb 18 22:50:41.954: Vi1 CHAP: Unable to authenticate for peer
*Feb 18 22:50:43.970: Vi1 PPP: Authorization required


On R2:-
username R2 password 0 ipexpert

interface Serial0/0/0.24 point-to-point
 frame-relay interface-dlci 204 ppp Virtual-Template1

interface Serial0/0/0.24 point-to-point
 frame-relay interface-dlci 204 ppp Virtual-Template1

R2#
*Feb 18 22:59:49.200: Vi1 CHAP: O CHALLENGE id 247 len 23 from "R2"
*Feb 18 22:59:49.200: Vi1 CHAP: I CHALLENGE id 165 len 23 from "R4"
*Feb 18 22:59:49.200: Vi1 CHAP: Unable to authenticate for peer
*Feb 18 22:59:51.216: Vi1 PPP: Authorization required
*Feb 18 22:59:53.232: Vi1 CHAP: O CHALLENGE id 248 len 23 from "R2"
*Feb 18 22:59:53.232: Vi1 CHAP: I CHALLENGE id 166 len 23 from "R4"
*Feb 18 22:59:53.232: Vi1 CHAP: Unable to authenticate for peer
*Feb 18 22:59:55.248: Vi1 PPP: Authorization required