Index: channels/chan_iax2.c
===================================================================
--- channels/chan_iax2.c	(revision 80048)
+++ channels/chan_iax2.c	(working copy)
@@ -2913,7 +2913,7 @@
 	char mohsuggest[MAX_MUSICCLASS];
 };
 
-static int create_addr(const char *peername, struct sockaddr_in *sin, struct create_addr_info *cai)
+static int create_addr(const char *peername, struct ast_channel *c, struct sockaddr_in *sin, struct create_addr_info *cai)
 {
 	struct iax2_peer *peer;
 
@@ -2921,6 +2921,7 @@
 	cai->sockfd = defaultsockfd;
 	cai->maxtime = 0;
 	sin->sin_family = AF_INET;
+	struct ast_codec_pref ourprefs;
 
 	if (!(peer = find_peer(peername, 1))) {
 		cai->found = 0;
@@ -2930,7 +2931,11 @@
 		}
 		sin->sin_port = htons(IAX_DEFAULT_PORTNO);
 		/* use global iax prefs for unknown peer/user */
-		ast_codec_pref_convert(&prefs, cai->prefs, sizeof(cai->prefs), 1);
+		/* But move the calling channel's native codec to the top of the preference list */
+		memcpy(&ourprefs, &prefs, sizeof(ourprefs));
+		if (c)
+			ast_codec_pref_prepend(&ourprefs, c->nativeformats, 1);
+		ast_codec_pref_convert(&ourprefs, cai->prefs, sizeof(cai->prefs), 1);
 		return 0;
 	}
 
@@ -2956,7 +2961,13 @@
 	cai->encmethods = peer->encmethods;
 	cai->sockfd = peer->sockfd;
 	cai->adsi = peer->adsi;
-	ast_codec_pref_convert(&peer->prefs, cai->prefs, sizeof(cai->prefs), 1);
+	memcpy(&ourprefs, &peer->prefs, sizeof(ourprefs));
+	/* Move the calling channel's native codec to the top of the preference list */
+	if (c) {
+		ast_log(LOG_DEBUG, "prepending %x to prefs\n", c->nativeformats);
+		ast_codec_pref_prepend(&ourprefs, c->nativeformats, 1);
+	}
+	ast_codec_pref_convert(&ourprefs, cai->prefs, sizeof(cai->prefs), 1);
 	ast_copy_string(cai->context, peer->context, sizeof(cai->context));
 	ast_copy_string(cai->peercontext, peer->peercontext, sizeof(cai->peercontext));
 	ast_copy_string(cai->username, peer->username, sizeof(cai->username));
@@ -3134,7 +3145,7 @@
 	if (!pds.exten)
 		pds.exten = defaultrdest;
 
-	if (create_addr(pds.peer, &sin, &cai)) {
+	if (create_addr(pds.peer, c, &sin, &cai)) {
 		ast_log(LOG_WARNING, "No address associated with '%s'\n", pds.peer);
 		return -1;
 	}
@@ -8806,7 +8817,7 @@
 	if (end) {
 		memcpy(&sin, end, sizeof(sin));
 		cai.sockfd = sockfd;
-	} else if (create_addr(dest, &sin, &cai))
+	} else if (create_addr(dest, NULL, &sin, &cai))
 		return -1;
 
 	/* Build the rest of the message */
@@ -9007,7 +9018,7 @@
 	       
 	
 	/* Populate our address from the given */
-	if (create_addr(pds.peer, &sin, &cai)) {
+	if (create_addr(pds.peer, NULL, &sin, &cai)) {
 		*cause = AST_CAUSE_UNREGISTERED;
 		return NULL;
 	}
@@ -10378,7 +10389,7 @@
 	parse_dial_string(tmpstr, &pds);
 
 	/* Populate our address from the given */
-	if (create_addr(pds.peer, &sin, &cai))
+	if (create_addr(pds.peer, NULL, &sin, &cai))
 		return -1;
 
 	ast_debug(1, "peer: %s, username: %s, password: %s, context: %s\n",
Index: main/frame.c
===================================================================
--- main/frame.c	(revision 80048)
+++ main/frame.c	(working copy)
@@ -1024,7 +1024,7 @@
 /*! \brief Append codec to list */
 int ast_codec_pref_append(struct ast_codec_pref *pref, int format)
 {
-	int x, newindex = -1;
+	int x, newindex = 0;
 
 	ast_codec_pref_remove(pref, format);
 
@@ -1047,7 +1047,44 @@
 	return x;
 }
 
+/*! \brief Prepend codec to list */
+void ast_codec_pref_prepend(struct ast_codec_pref *pref, int format, int only_if_existing)
+{
+	int x, newindex = 0;
 
+	/* First step is to get the codecs "index number" */
+	for (x = 0; x < sizeof(AST_FORMAT_LIST) / sizeof(AST_FORMAT_LIST[0]); x++) {
+		if (AST_FORMAT_LIST[x].bits == format) {
+			newindex = x + 1;
+			break;
+		}
+	}
+	/* Done if its unknown */
+	if (newindex == 0)
+		return;
+
+	/* Now find any existing occurrence, or the end */
+	for (x = 0; x < 32; x++) {
+		if (pref->order[x] == 0 || pref->order[x] == newindex)
+			break;
+	}
+
+	if (only_if_existing && (pref->order[x] == 0))
+		return;
+
+	/* Move down to make space to insert - either all the way to the end,
+	   or as far as the existing location (which will be overwritten) */
+	for (; x > 0; x--) {
+		pref->order[x] = pref->order[x-1];
+		pref->framing[x] = pref->framing[x-1];
+	}
+
+	/* And insert the new entry */
+	pref->order[0] = newindex;
+	pref->framing[0] = 0; /* ? */
+}
+
+
 /*! \brief Set packet size for codec */
 int ast_codec_pref_setsize(struct ast_codec_pref *pref, int format, int framems)
 {
Index: include/asterisk/frame.h
===================================================================
--- include/asterisk/frame.h	(revision 80048)
+++ include/asterisk/frame.h	(working copy)
@@ -527,6 +527,10 @@
 */
 int ast_codec_pref_append(struct ast_codec_pref *pref, int format);
 
+/*! \brief Prepend an audio codec to a preference list, removing it first if it was already there 
+*/
+void ast_codec_pref_prepend(struct ast_codec_pref *pref, int format, int only_if_existing);
+
 /*! \brief Select the best audio format according to preference list from supplied options. 
    If "find_best" is non-zero then if nothing is found, the "Best" format of 
    the format list is selected, otherwise 0 is returned. */