Some of the code to map Jingle reasons to Tp errors seems rather suspicious:

> + case JINGLE_REASON_GONE:
> + /* This one is only in the media channel, we don't have a
> + * Call reason to match */
> + call_reason = TP_CALL_STATE_CHANGE_REASON_UNKNOWN;
> + break;

Doesn't that mean we should add a Call reason, or at least a detailed D-Bus error string?

> + case JINGLE_REASON_EXPIRED:
> + /* No matching error in our spec */
> + call_reason = TP_CALL_STATE_CHANGE_REASON_UNKNOWN;
> + break;

Ditto

> + case JINGLE_REASON_GENERAL_ERROR:
> + call_reason = TP_CALL_STATE_CHANGE_REASON_SERVICE_ERROR;
> + break;

Is this really the right mapping?

> + case JINGLE_REASON_UNSUPPORTED_TRANSPORTS:
> + call_reason = TP_CALL_STATE_CHANGE_REASON_NETWORK_ERROR;
> + break;

Ditto

> + case JINGLE_REASON_SECURITY_ERROR:
> + call_reason = TP_CALL_STATE_CHANGE_REASON_CONNECTIVITY_ERROR;
> + break;

Ditto

> + case JINGLE_REASON_ALTERNATIVE_SESSION:
> + break;

Is Unknown really the best we can do here?