I did some tests with auth_ephemeral. When timestamp has expired, I get to syslog
Feb 23 03:53:05 char /usr/bin/sip-proxy[31758]: WARNING: auth_ephemeral [authorize.c:205]: autheph_verify_timestamp(): username has expired Feb 23 03:53:05 char /usr/bin/sip-proxy[31758]: ERROR: auth_ephemeral [authorize.c:260]: digest_authenticate(): invalid timestamp in username
In my opinion, the WARNING is enough and the ERROR message should be removed. ERROR is when an error happens. There is no error here, just an expired timestamp.
-- Juha