Index: channels/chan_sip.c
===================================================================
--- channels/chan_sip.c	(revision 137846)
+++ channels/chan_sip.c	(working copy)
@@ -8079,8 +8079,7 @@
 	return TRUE;		
 }
 
-/*! \brief Change the other partys IP address based on given contact */
-static int set_address_from_contact(struct sip_pvt *pvt)
+static int __set_address_from_contact(const char *fullcontact, struct sockaddr_in *sin)
 {
 	struct hostent *hp;
 	struct ast_hostent ahp;
@@ -8089,15 +8088,8 @@
 	char contact_buf[256];
 	char *contact;
 
-	if (ast_test_flag(&pvt->flags[0], SIP_NAT_ROUTE)) {
-		/* NAT: Don't trust the contact field.  Just use what they came to us
-		   with. */
-		pvt->sa = pvt->recv;
-		return 0;
-	}
-
 	/* Work on a copy */
-	ast_copy_string(contact_buf, pvt->fullcontact, sizeof(contact_buf));
+	ast_copy_string(contact_buf, fullcontact, sizeof(contact_buf));
 	contact = contact_buf;
 
 	/* Make sure it's a SIP URL */
@@ -8134,14 +8126,27 @@
 		ast_log(LOG_WARNING, "Invalid host name in Contact: (can't resolve in DNS) : '%s'\n", host);
 		return -1;
 	}
-	pvt->sa.sin_family = AF_INET;
-	memcpy(&pvt->sa.sin_addr, hp->h_addr, sizeof(pvt->sa.sin_addr));
-	pvt->sa.sin_port = htons(port);
+	sin->sin_family = AF_INET;
+	memcpy(&sin->sin_addr, hp->h_addr, sizeof(sin->sin_addr));
+	sin->sin_port = htons(port);
 
 	return 0;
 }
 
+/*! \brief Change the other partys IP address based on given contact */
+static int set_address_from_contact(struct sip_pvt *pvt)
+{
+	if (ast_test_flag(&pvt->flags[0], SIP_NAT_ROUTE)) {
+		/* NAT: Don't trust the contact field.  Just use what they came to us
+		   with. */
+		pvt->sa = pvt->recv;
+		return 0;
+	}
 
+	return __set_address_from_contact(pvt->fullcontact, &pvt->sa);
+}
+
+
 /*! \brief Parse contact header and save registration (peer registration) */
 static enum parse_register_result parse_register_contact(struct sip_pvt *pvt, struct sip_peer *peer, struct sip_request *req)
 {
@@ -17220,6 +17225,12 @@
 	}
 	if (!ast_strlen_zero(fullcontact)) {
 		ast_copy_string(peer->fullcontact, fullcontact, sizeof(peer->fullcontact));
+		/* We have a hostname in the fullcontact, but if we don't have an
+		 * address listed on the entry (or if it's 'dynamic'), then we need to
+		 * parse the entry to obtain the IP address, so a dynamic host can be
+		 * contacted immediately after reload (as opposed to waiting for it to
+		 * register once again). */
+		__set_address_from_contact(fullcontact, &peer->addr);
 	}
 
 	if (!ast_test_flag(&global_flags[1], SIP_PAGE2_IGNOREREGEXPIRE) && ast_test_flag(&peer->flags[1], SIP_PAGE2_DYNAMIC) && realtime) {