diff --git a/conf/sip_profiles/external.xml b/conf/sip_profiles/external.xml
index 1d7bae9a7d..81f8e4a61c 100644
--- a/conf/sip_profiles/external.xml
+++ b/conf/sip_profiles/external.xml
@@ -32,6 +32,7 @@
     <param name="hold-music" value="$${hold_music}"/>
     <param name="rtp-timer-name" value="soft"/>
     <!--<param name="enable-100rel" value="true"/>-->
+    <!--<param name="disable-srv503" value="true"/>-->                
     <!-- This could be set to "passive" -->
     <param name="local-network-acl" value="localnet.auto"/>
     <param name="manage-presence" value="false"/>
diff --git a/conf/sip_profiles/internal-ipv6.xml b/conf/sip_profiles/internal-ipv6.xml
index 37ff58b310..ee27a241a0 100644
--- a/conf/sip_profiles/internal-ipv6.xml
+++ b/conf/sip_profiles/internal-ipv6.xml
@@ -24,6 +24,7 @@
     <param name="sip-ip" value="$${local_ip_v6}"/>
     <param name="hold-music" value="$${hold_music}"/>
     <!--<param name="enable-100rel" value="false"/>-->
+    <!--<param name="disable-srv503" value="true"/>-->
     <param name="apply-inbound-acl" value="domains"/>
     <!--<param name="apply-register-acl" value="domains"/>-->
     <!--<param name="dtmf-type" value="info"/>-->
diff --git a/conf/sip_profiles/internal.xml b/conf/sip_profiles/internal.xml
index 3b19b6ecc6..629019fbf4 100644
--- a/conf/sip_profiles/internal.xml
+++ b/conf/sip_profiles/internal.xml
@@ -102,6 +102,11 @@
 	It is not recommended to enable 100rel at this time.
     -->
     <!--<param name="enable-100rel" value="true"/>-->
+
+    <!-- uncomment if you don't wish to try a next SRV destination on 503 response -->
+    <!-- RFC3263 Section 4.3 -->	    
+    <!--<param name="disable-srv503" value="true"/>-->    
+    
     <!-- Enable Compact SIP headers. -->
     <!--<param name="enable-compact-headers" value="true"/>-->
     <!--