== Parsing '/etc/asterisk/modem.conf': Found
  == Loading modem driver chan_modem_i4l.soOct  7 14:40:14 WARNING[-1222241632]: loader.c:248 ast_load_resource: /usr/lib/asterisk/modules/chan_modem_i4l.so: undefined symbol: ast_unregister_modem_driver
Oct  7 14:40:14 ERROR[-1222241632]: chan_modem.c:955 load_module: Failed to load driver chan_modem_i4l.so
  == Unregistered channel type 'Modem'
Oct  7 14:40:14 WARNING[-1222241632]: loader.c:334 ast_load_resource: chan_modem.so: load_module failed, returning -1
  == Unregistered channel type 'Modem'
Oct  7 14:40:14 WARNING[-1222241632]: loader.c:429 load_modules: Loading module chan_modem.so failed!
[root@king-coco asterisk]# fgrep modem *
modem.conf.old:;driver=aopen    ; modem by AOpen
modem.conf.old:; particularly if asterisk does not know about our kind of modem.
modules.conf:; Explicitly load the chan_modem.so early on to be sure
modules.conf:; it loads before any of the chan_modem_* 's afte rit
modules.conf:;load => chan_modem.so
modules.conf:chan_modem.so=no