enable auto-nat by default

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@13618 d0543943-73ff-0310-b7d9-9358b9ac24b2

conf/sip_profiles/internal.xml

@@ -151,8 +151,9 @@
 	auto     - Use guessed ip.
 	auto-nat - Use ip learned from NAT-PMP or UPNP
     -->
-    <!-- <param name="ext-rtp-ip" value="$${external_rtp_ip}"/> -->
-    <!-- <param name="ext-sip-ip" value="$${external_sip_ip}"/> -->
+    <param name="ext-rtp-ip" value="auto-nat"/>
+    <param name="ext-sip-ip" value="auto-nat"/>
+
     <!-- rtp inactivity timeout -->
     <param name="rtp-timeout-sec" value="300"/>
     <param name="rtp-hold-timeout-sec" value="1800"/>