Got a Cisco Sipura SPA 941 hardware phone and I am connected to Asterix (most likely) VoIP server of my provider.
I am behind a firewall (ADSL) and I have put my phone to the DMZ zone, so it should be reachable from the internet.
Now I can make calls without any problems, but when somebody calls me I can hear it ringing, but when I pickup the earphone, nothing happens and I see "Answering Call" on the display. On the other side of the line I still hear its ringing.
Now question to all superuser VoIP experts: what option should I search on my phone to chage to get this working? My friend gave me advice DMTF (got Auto), tried all options without any luck.