Mira en la página anterior ( botón previus page) porque lo que se ve ahí es cuando la caída ya ha tenido lugar y empieza la nueva sesión. Tienes que ver algo así
Sun, 2009-10-11 16:52:09 - Terminating on signal 15.
Sun, 2009-10-11 16:52:09 - chld,got_sigchld=1
Sun, 2009-10-11 16:52:09 - run_program(/etc/ppp/ip-down)
Sun, 2009-10-11 16:52:09 - ret=6571
Sun, 2009-10-11 16:52:09 - Couldn't increase MTU to 1500.
Sun, 2009-10-11 16:52:09 - Couldn't increase MRU to 1500
Sun, 2009-10-11 16:52:09 - reap_kids,waitfor=0
Sun, 2009-10-11 16:52:10 - Modem hangup
Sun, 2009-10-11 16:52:10 - Connection terminated.
Sun, 2009-10-11 16:52:10 - Connect time 233.3 minutes.
Sun, 2009-10-11 16:52:10 - Sent 25637433 bytes, received 78643491 bytes.
Sun, 2009-10-11 16:52:10 - Doing disconnect
Sun, 2009-10-11 16:52:10 - sendto returned:
Sun, 2009-10-11 16:52:10 - Exit.
Sun, 2009-10-11 16:52:43 - Plugin pppoe loaded.
Sun, 2009-10-11 16:52:43 - PPPoE Plugin Initialized
Sun, 2009-10-11 16:52:43 - Plugin pppoe called.
Sun, 2009-10-11 16:52:43 - Bad device name: escape (Unknown error 19)
Sun, 2009-10-11 16:52:43 - Bad device name: multilink (Unknown error 19)
Sun, 2009-10-11 16:52:43 - Bad device name: local (Unknown error 19)
Sun, 2009-10-11 16:52:43 - Bad device name: sync (Unknown error 19)
Sun, 2009-10-11 16:52:43 - Bad device name: vj (Unknown error 19)
Sun, 2009-10-11 16:52:43 - pppd 2.4.1 started by root, uid 0
Sun, 2009-10-11 16:52:43 - setting line discipline hook
Sun, 2009-10-11 16:52:43 - Sending PADI
Sun, 2009-10-11 16:52:44 - Sending PADI 1...
Sun, 2009-10-11 16:52:46 - Sending PADI 2...
Sun, 2009-10-11 16:52:50 - Sending PADI 3...
Sun, 2009-10-11 16:52:58 - Sending PADI 4...
Sun, 2009-10-11 16:53:18 - HOST_UNIQ successful match
----------------------------------------------salto aquí y paso a otra página
Sun, 2009-10-11 16:53:22 - primary DNS address 87.216.1.65
Sun, 2009-10-11 16:53:22 - secondary DNS address 87.216.1.66
Sun, 2009-10-11 16:53:22 - run_program(/etc/ppp/ip-up)
Sun, 2009-10-11 16:53:22 - record_child
Sun, 2009-10-11 16:53:22 - record_child,pid=6726
Sun, 2009-10-11 16:53:22 - return pid=6726
Sun, 2009-10-11 16:53:31 - chld,got_sigchld=1
Sun, 2009-10-11 16:53:31 - reap_kids,waitfor=0
Sun, 2009-10-11 16:53:31 - reap_kids:pid=6726
Sí, lo de la ip asignada a cada ordenador y poner dns manualmente es eso :)
En cualquier caso parece que ser que no se puede seleccionar el tipo de encapsulación recomendado por el propio fabricante, no solo para Telefónica sino también para Jazztel 20 megas :-O