Asterisk SIP MESSAGE Routing

sip.conf

[general]
...
accept_outofcall_message=yes
outofcall_message_context=messages
auth_message_requests=yes
regcontext=sipregistrations
...

[17735550001]
...
regexten=2201&17735550001
...

[17735550002]
...
regexten=2202&17735550002
...

extensions.conf

[messages]
include => sipregistrations

; Country Code +1 extensions which match sip peer names only at the moment
exten => _1NXXNXXXXXX,2,MessageSend(sip:${EXTEN},${MESSAGE(from)})
same => n,NoOp(Message Send Status: ${MESSAGE_SEND_STATUS})
same => n,Hangup()