problème utilisateur inconnu pour le VPN...

[bibiwan14]

bonsoir, voila j'ai voulu lancer un VPN avec ma SME, j'ai clairement donné l'autorisation a un compte de s'y connecter... donné plus d'un utilisateur pour les accés PPTP... mais sur le poste client un message est envoyé comme quoi l'utilisateur est inconnu !!!

j'ai récupéré le log sur le serveur, voila ce que ca donne :

Jul 17 20:43:12 serveur pptpd[9353]: MGR: Launching /usr/sbin/pptpctrl to handle client
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: local address = 192.168.0.1
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: remote address = 192.168.0.248
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: pppd speed = 460800
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: pppd options file = /etc/ppp/options.pptpd
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: Client 82.253.188.109 control connection started
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: Received PPTP Control Message (type: 1)
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: Made a START CTRL CONN RPLY packet
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: I wrote 156 bytes to the client.
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: Sent packet to client
Jul 17 20:43:12 serveur esmith::event[9350]: S15set-external-ip=action|Event|ip-change|Action|S15set-external-ip|Start|1121625791 299204|End|1121625792 188262|Elapsed|0.889058
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: Received PPTP Control Message (type: 7)
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: Set parameters to 100000000 maxbps, 64 window size
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: Made a OUT CALL RPLY packet
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: Starting call (launching pppd, opening GRE)
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: pty_fd = 7
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: tty_fd = 8
Jul 17 20:43:12 serveur pptpd[9354]: CTRL (PPPD Launcher): program binary = /usr/sbin/pppd
Jul 17 20:43:12 serveur pptpd[9354]: CTRL (PPPD Launcher): local address = 192.168.0.1
Jul 17 20:43:12 serveur pptpd[9354]: CTRL (PPPD Launcher): remote address = 192.168.0.248
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: I wrote 32 bytes to the client.
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: Sent packet to client
Jul 17 20:43:12 serveur esmith::event[9350]: Running event handler: /etc/e-smith/events/ip-change/S85update-dns
Jul 17 20:43:12 serveur pppd[9354]: Plugin radius.so loaded.
Jul 17 20:43:12 serveur pppd[9354]: RADIUS plugin initialized.
Jul 17 20:43:12 serveur pppd[9354]: pppd 2.4.3 started by root, uid 0
Jul 17 20:43:12 serveur pppd[9354]: Starting negotiation on /dev/pts/1
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: Received PPTP Control Message (type: 15)
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: Got a SET LINK INFO packet with standard ACCMs
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: Received PPTP Control Message (type: 15)
Jul 17 20:43:12 serveur pptpd[9353]: CTRL: Ignored a SET LINK INFO packet with real ACCMs!
Jul 17 20:43:12 serveur pppd[9354]: rc_map2id: can't find tty /dev/ in map database
Jul 17 20:43:13 serveur esmith::event[9350]: S85update-dns=action|Event|ip-change|Action|S85update-dns|Start|1121625792 198976|End|1121625793 113495|Elapsed|0.914519
Jul 17 20:43:13 serveur esmith::event[9350]: Running event handler: /etc/e-smith/events/actions/adjust-services
Jul 17 20:43:14 serveur esmith::event[9350]: adjusting pptpd (sigterm)
Jul 17 20:43:14 serveur pptpd[9357]: MGR: Manager process started
Jul 17 20:43:14 serveur pptpd[9357]: MGR: Maximum of 3 connections available
Jul 17 20:43:14 serveur esmith::event[9350]: adjusting qmail (sighup)
Jul 17 20:43:14 serveur esmith::event[9350]: adjusting masq (adjust)
Jul 17 20:43:14 serveur pppd[9354]: Peer mad failed CHAP authentication
Jul 17 20:43:14 serveur pptpd[9353]: CTRL: Received PPTP Control Message (type: 15)
Jul 17 20:43:14 serveur pptpd[9353]: CTRL: Got a SET LINK INFO packet with standard ACCMs
Jul 17 20:43:14 serveur pppd[9354]: Connection terminated.
Jul 17 20:43:14 serveur pppd[9354]: Exit.
Jul 17 20:43:14 serveur pptpd[9353]: GRE: read(fd=7,buffer=804d5a0,len=8196) from PTY failed: status = -1 error = Input/output error, usually caused by unexpected termination of pppd, check option syntax and pppd logs
Jul 17 20:43:14 serveur pptpd[9353]: CTRL: PTY read or GRE write failed (pty,gre)=(7,8)
Jul 17 20:43:14 serveur pptpd[9353]: CTRL: Reaping child PPP[9354]
Jul 17 20:43:14 serveur pptpd[9353]: CTRL: Client 82.253.188.109 control connection finished
Jul 17 20:43:14 serveur pptpd[9353]: CTRL: Exiting now

VOila !!!! quelqu'un peut m'aider ?...
Edit : je pense qu'il doit y'avoir une erreur avec ce qui concerne l'authentification CHAP.... quelqu'un peut m'expliquer qu'est ce que c'est ? comment régler ce ptit soucis ?