We haven't done systematic testing of Fargo with various SIP clients and servers, or with various XMPP clients.
Repurposing this bug for short-term targets: XMPP clients: Gabble XMPP server: ejabberd SIP servers: OpenSER (simple SIP server for testing) and genuine SIP server SIP peer: telepathy-sofiasip and a hardware SIP phone (Others: SIP peer (gateway): alsuren has tested with voipuser.org. SIP servers: smcv has tested with voxalot and sipphone.) Estimated time 15h including potential tweaking for compatibility.
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