diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index 68f382e42359ec867d33a86d9b71ee9f7952ccb0..5b7c0401ebab8c1e5205e6d603c77e8991cb36d8 100644
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -7747,7 +7747,7 @@ static const char *dtmfmode2str(int mode)
 {
 	switch (mode) {
 	case SIP_DTMF_RFC2833:
-		return "rtp";
+		return "rfc2833";
 	case SIP_DTMF_INFO:
 		return "info";
 	case SIP_DTMF_INBAND:
@@ -11723,7 +11723,7 @@ static int handle_common_options(struct ast_flags *flags, struct ast_flags *mask
 		ast_clear_flag(flags, SIP_DTMF);
 		if (!strcasecmp(v->value, "inband"))
 			ast_set_flag(flags, SIP_DTMF_INBAND);
-		else if (!strcasecmp(v->value, "rfc2833") || !strcasecmp(v->value, "rtp"))
+		else if (!strcasecmp(v->value, "rfc2833"))
 			ast_set_flag(flags, SIP_DTMF_RFC2833);
 		else if (!strcasecmp(v->value, "info"))
 			ast_set_flag(flags, SIP_DTMF_INFO);
@@ -12848,7 +12848,7 @@ static int sip_set_rtp_peer(struct ast_channel *chan, struct ast_rtp *rtp, struc
 }
 
 static char *synopsis_dtmfmode = "Change the dtmfmode for a SIP call";
-static char *descrip_dtmfmode = "SIPDtmfMode(inband|info|rtp): Changes the dtmfmode for a SIP call\n";
+static char *descrip_dtmfmode = "SIPDtmfMode(inband|info|rfc2833): Changes the dtmfmode for a SIP call\n";
 static char *app_dtmfmode = "SIPDtmfMode";
 
 static char *app_sipaddheader = "SIPAddHeader";
@@ -12871,7 +12871,7 @@ static int sip_dtmfmode(struct ast_channel *chan, void *data)
 	if (data)
 		mode = (char *)data;
 	else {
-		ast_log(LOG_WARNING, "This application requires the argument: info, inband, rtp\n");
+		ast_log(LOG_WARNING, "This application requires the argument: info, inband, rfc2833\n");
 		return 0;
 	}
 	ast_mutex_lock(&chan->lock);
@@ -12889,10 +12889,10 @@ static int sip_dtmfmode(struct ast_channel *chan, void *data)
 	if (!strcasecmp(mode,"info")) {
 		ast_clear_flag(p, SIP_DTMF);
 		ast_set_flag(p, SIP_DTMF_INFO);
-	} else if (!strcasecmp(mode, "rfc2833") || !strcasecmp(mode, "rtp")) {
+	} else if (!strcasecmp(mode,"rfc2833")) {
 		ast_clear_flag(p, SIP_DTMF);
 		ast_set_flag(p, SIP_DTMF_RFC2833);
-	} else if (!strcasecmp(mode, "inband")) { 
+	} else if (!strcasecmp(mode,"inband")) { 
 		ast_clear_flag(p, SIP_DTMF);
 		ast_set_flag(p, SIP_DTMF_INBAND);
 	} else
diff --git a/configs/sip.conf.sample b/configs/sip.conf.sample
index d8a1893a2ae2e67bd524671b8ef7059f2357eb6c..72bfcb5a8dfb4f5a48807836f83370dfbb5dafb2 100644
--- a/configs/sip.conf.sample
+++ b/configs/sip.conf.sample
@@ -96,12 +96,11 @@ srvlookup=yes			; Enable DNS SRV lookups on outbound calls
        	                	; of performing a "hairpin" call.
 ;usereqphone = no		; If yes, ";user=phone" is added to uri that contains
 				; a valid phone number
-;dtmfmode = rtp			; Set default dtmfmode for sending DTMF. Default is rtp (according to RFC 2833)
+;dtmfmode = rfc2833		; Set default dtmfmode for sending DTMF. Default: rfc2833
 				; Other options: 
-				; info		SIP INFO messages
-				; inband	Inband audio
-				;		(requires 64 kbit codec -alaw, ulaw)
-				; auto : Use rtp if offered, inband otherwise
+				; info : SIP INFO messages
+				; inband : Inband audio (requires 64 kbit codec -alaw, ulaw)
+				; auto : Use rfc2833 if offered, inband otherwise
 
 ;compactheaders = yes		; send compact sip headers.
 ;sipdebug = yes			; Turn on SIP debugging by default, from
@@ -413,7 +412,7 @@ srvlookup=yes			; Enable DNS SRV lookups on outbound calls
 ;subscribecontext=localextensions	; Only allow SUBSCRIBE for local extensions
 ;language=de			; Use German prompts for this user 
 ;host=dynamic			; This peer register with us
-;dtmfmode=inband		; Choices are inband, rtp, or info
+;dtmfmode=inband		; Choices are inband, rfc2833, or info
 ;defaultip=192.168.0.59		; IP used until peer registers
 ;mailbox=1234@context,2345      ; Mailbox(-es) for message waiting indicator
 ;vmexten=voicemail      ; dialplan extension to reach mailbox 
@@ -429,7 +428,7 @@ srvlookup=yes			; Enable DNS SRV lookups on outbound calls
 ;context=from-sip		; Context for incoming calls from this user
 ;secret=blahpoly
 ;host=dynamic			; This peer register with us
-;dtmfmode=rtp			; Choices are inband, rtp, or info
+;dtmfmode=rfc2833		; Choices are inband, rfc2833, or info
 ;username=polly			; Username to use in INVITE until peer registers
 				; Normally you do NOT need to set this parameter
 ;disallow=all