After many attempts ,these are the settings:
1.Two External extensions(WAN):Extension 100(for example)
2.General Settings: Asterisk Dial command options- r
3.IN FreePBX: Asrerisk SIP Setting: NAT-yes
** My system behind a router(NAT).
Note: If you use "info" you can't dial DTMF in SIP, which means you can't enter voice mail password and IVR calls.
X-Lite (Softphone) don't works with INFO only RFC2833, YEALINK (T28) Auto+Sip INFO
Two External Softphone
(X-lite)need to set in the Account Setting in the Presence tab
,no Peer-to-Peer (Still possible to work with rfc2833)