[asterisk-users] From address missing 'sip:', using it anyway

[motty.cruz]

Hello, 
I see the following error in the logs

[Jan  4 11:37:35] NOTICE[21]: chan_sip.c:15388 check_user_full: From address
missing 'sip:', using it anyway

Does anybody know how to stop this error? It does not seem to be affecting
performance on the Asterisk 1.8.4.1 running on Centos Linux 2.6. I have
google it but empty! 

Thanks, 
Celso