asterisk users - Jun 2005 - chan_sip.c: Maximum retries exceeded on call ........ for seqno 1 01 (Non-critical Response)

Every now and again we are receiving this error in our logs:

Jun 14 15:54:42 WARNING[11137] chan_sip.c: Maximum retries exceeded on call
FDADCC70-DC4411D9-9FCED9C5-C4BC6369@213.199.36.50 for seqno 101
(Non-critical Response)

We resolved a previous issue of this type but that was a "Critical
Response"
and occurred due to bad forwarding from a SER server.

Is the Non-critical response something to worry about?

Thanks!