Index: channels/chan_sip.c
===================================================================
--- channels/chan_sip.c	(revision 13281)
+++ channels/chan_sip.c	(working copy)
@@ -2981,6 +2981,9 @@
 	for (v = i->chanvars ; v ; v = v->next)
 		pbx_builtin_setvar_helper(tmp,v->name,v->value);
 				
+	if (ast_test_flag (i, SIP_DTMF_INFO))
+		tmp->dtmf_nbridge = 1;
+		
 	return tmp;
 }
 
Index: include/asterisk/channel.h
===================================================================
--- include/asterisk/channel.h	(revision 13281)
+++ include/asterisk/channel.h	(working copy)
@@ -372,6 +372,8 @@
 	char dtmfq[AST_MAX_EXTENSION];		
 	/*! DTMF frame */
 	struct ast_frame dtmff;			
+	/*! Alternative dtmf source can do native bridge, defaults to false */
+	unsigned char dtmf_nbridge;
 
 	/*! PBX private structure */
 	struct ast_pbx *pbx;
Index: rtp.c
===================================================================
--- rtp.c	(revision 13281)
+++ rtp.c	(working copy)
@@ -1582,8 +1582,9 @@
 	memset(&vac0, 0, sizeof(vac0));
 	memset(&vac1, 0, sizeof(vac1));
 
-	/* if need DTMF, cant native bridge */
-	if (flags & (AST_BRIDGE_DTMF_CHANNEL_0 | AST_BRIDGE_DTMF_CHANNEL_1))
+	/* if need DTMF, and dtmf_nbridge=0,  cant native bridge */
+	if ( ((flags & AST_BRIDGE_DTMF_CHANNEL_0) && !(c0->dtmf_nbridge)) || 
+			((flags & AST_BRIDGE_DTMF_CHANNEL_1) && !(c1->dtmf_nbridge)))  
 		return AST_BRIDGE_FAILED_NOWARN;
 
 	/* Lock channels */