Comment 476 for bug 191889

Ubuntu 12.10
Linux eb 3.5.0-27-generic #46-Ubuntu SMP Mon Mar 25 20:00:05 UTC 2013 i686 i686 i686 GNU/Linux
USB modem: Product: Vertex Wireless Multi-Function Device

The connection is OK but after every 50 minutes the modem hangups:

May 3 15:36:05 eb pppd[3589]: LCP terminated by peer
May 3 15:36:05 eb pppd[3589]: Connect time 51.1 minutes.
May 3 15:36:05 eb pppd[3589]: Sent 1768732 bytes, received 55238638 bytes.
May 3 15:36:09 eb pppd[3589]: Connection terminated.
May 3 15:36:09 eb NetworkManager[1189]: <info> (ttyACM0): device state change: activated -> failed (reason 'ip-config-unavailable') [100 120 5]
May 3 15:36:09 eb avahi-daemon[1159]: Withdrawing workstation service for ppp0.
May 3 15:36:09 eb NetworkManager[1189]: <info> Unmanaged Device found; state CONNECTED forced. (see http://bugs.launchpad.net/bugs/191889)
May 3 15:36:09 eb NetworkManager[1189]: <warn> Activation (ttyACM0) failed for connection 'UFON 910 045 174'
....

Sometimes the modem falls out after some minutes:
May 3 15:40:24 eb NetworkManager[1189]: <info> Unmanaged Device found; state CONNECTED forced. (see http://bugs.launchpad.net/bugs/191889)
May 3 15:41:14 eb pppd[5438]: Modem hangup
May 3 15:41:14 eb pppd[5438]: Connect time 4.1 minutes.
May 3 15:41:14 eb pppd[5438]: Sent 141041 bytes, received 1393940 bytes.
...

On another netbook with Ubuntu 12.04 LTS this modem runs many hours without problems.
See Attachment for syslog