As it says into this readme (http://downloads.digium.com/pub/telepho ... isk/README
) ...A Skype For Asterisk key must be re-registered if any of the Ethernet
devices in your Asterisk server are changed, added, or removed. The
unique Skype For Asterisk license file which is located in your
/var/lib/asterisk/licenses directory is tied to the MAC address of all
the Ethernet devices installed in your system. A Skype For Asterisk key
can only be re-registered once without authorization from Digium.
Digium must be contacted by phone in order to request authorization to
have your Skype For Asterisk key incremented. Digium reserves the right to
deny authorization for having a Skype For Asterisk key incremented....
I've ask authorization to Digium to reinstall SFA, and so I was able to reinstall SFA.
Now all works fine.