diff -Naur asterisk-1.8.0/channels/chan_sip.c asterisk-1.8.0/channels/chan_sip.c
--- asterisk-1.8.0/channels/chan_sip.c	2010-10-15 16:12:04.000000000 -0400
+++ asterisk-1.8.0/channels/chan_sip.c	2010-12-12 18:42:56.000000000 -0500
@@ -206,6 +206,12 @@
 
 */
 
+/*
+  This version has been kluged by Alex Fink to allow a new dtmfmode "both"
+  that recognises both rfc2833 and inband, and sends inband ('cause we're 
+  sending for human consumption).
+*/
+
 #include "asterisk.h"
 
 ASTERISK_FILE_VERSION(__FILE__, "$Revision: 291942 $")
@@ -3960,12 +3966,17 @@
 	}
 
 	if ((ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_INBAND) ||
-            (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_AUTO)) {
+      (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_AUTO)) {
 		if (!p->rtp || ast_rtp_instance_dtmf_mode_set(p->rtp, AST_RTP_DTMF_MODE_INBAND)) {
 			features |= DSP_FEATURE_DIGIT_DETECT;
-                }
+    }
+	} else if ((ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_BOTH)) {
+		if (!p->rtp || ast_rtp_instance_dtmf_mode_set(p->rtp, AST_RTP_DTMF_MODE_BOTH)) {
+			features |= DSP_FEATURE_DIGIT_DETECT;
+    }
 	}
 
+
 	if (ast_test_flag(&p->flags[1], SIP_PAGE2_FAX_DETECT_CNG)) {
 		features |= DSP_FEATURE_FAX_DETECT;
 	}
@@ -4010,7 +4021,8 @@
 		break;
 	case AST_OPTION_DIGIT_DETECT:
 		if ((ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_INBAND) ||
-		    (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_AUTO)) {
+		    (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_AUTO) ||
+		    (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_BOTH)) {
 			char *cp = (char *) data;
 
 			ast_debug(1, "%sabling digit detection on %s\n", *cp ? "En" : "Dis", chan->name);
@@ -4799,7 +4811,7 @@
 	ast_rtp_instance_set_hold_timeout(dialog->rtp, global_rtpholdtimeout);
 
 	ast_rtp_instance_set_prop(dialog->rtp, AST_RTP_PROPERTY_RTCP, 1);
-	ast_rtp_instance_set_prop(dialog->rtp, AST_RTP_PROPERTY_DTMF, ast_test_flag(&dialog->flags[0], SIP_DTMF) == SIP_DTMF_RFC2833);
+	ast_rtp_instance_set_prop(dialog->rtp, AST_RTP_PROPERTY_DTMF, (ast_test_flag(&dialog->flags[0], SIP_DTMF) == SIP_DTMF_RFC2833) || (ast_test_flag(&dialog->flags[0], SIP_DTMF) == SIP_DTMF_BOTH));
 	ast_rtp_instance_set_prop(dialog->rtp, AST_RTP_PROPERTY_DTMF_COMPENSATE, ast_test_flag(&dialog->flags[1], SIP_PAGE2_RFC2833_COMPENSATE));
 
 	ast_rtp_instance_set_qos(dialog->rtp, global_tos_audio, global_cos_audio, "SIP RTP");
@@ -4860,7 +4872,7 @@
 	}
 
 	if (dialog->rtp) { /* Audio */
-		ast_rtp_instance_set_prop(dialog->rtp, AST_RTP_PROPERTY_DTMF, ast_test_flag(&dialog->flags[0], SIP_DTMF) == SIP_DTMF_RFC2833);
+		ast_rtp_instance_set_prop(dialog->rtp, AST_RTP_PROPERTY_DTMF, (ast_test_flag(&dialog->flags[0], SIP_DTMF) == SIP_DTMF_RFC2833 || ast_test_flag(&dialog->flags[0], SIP_DTMF) == SIP_DTMF_BOTH));
 		ast_rtp_instance_set_prop(dialog->rtp, AST_RTP_PROPERTY_DTMF_COMPENSATE, ast_test_flag(&dialog->flags[1], SIP_PAGE2_RFC2833_COMPENSATE));
 		ast_rtp_instance_set_timeout(dialog->rtp, peer->rtptimeout);
 		ast_rtp_instance_set_hold_timeout(dialog->rtp, peer->rtpholdtimeout);
@@ -4945,7 +4957,8 @@
 		dialog->timer_b = 64 * dialog->timer_t1;
 
 	if ((ast_test_flag(&dialog->flags[0], SIP_DTMF) == SIP_DTMF_RFC2833) ||
-	    (ast_test_flag(&dialog->flags[0], SIP_DTMF) == SIP_DTMF_AUTO))
+	    (ast_test_flag(&dialog->flags[0], SIP_DTMF) == SIP_DTMF_AUTO) ||
+	    (ast_test_flag(&dialog->flags[0], SIP_DTMF) == SIP_DTMF_BOTH))
 		dialog->noncodeccapability |= AST_RTP_DTMF;
 	else
 		dialog->noncodeccapability &= ~AST_RTP_DTMF;
@@ -6177,6 +6190,13 @@
 			res = -1; /* Tell Asterisk to generate inband indications */
 		}
 		break;
+  case SIP_DTMF_BOTH: // both sends inband, so people hear it
+		if (p->rtp && ast_rtp_instance_dtmf_mode_get(p->rtp) == AST_RTP_DTMF_MODE_BOTH) {
+			ast_rtp_instance_dtmf_begin(p->rtp, digit);
+		} else {
+			res = -1; /* Tell Asterisk to generate inband indications */
+		}
+		break;
 	case SIP_DTMF_RFC2833:
 		if (p->rtp)
 			ast_rtp_instance_dtmf_begin(p->rtp, digit);
@@ -6213,6 +6233,13 @@
 			res = -1; /* Tell Asterisk to stop inband indications */
 		}
 		break;
+  case SIP_DTMF_BOTH: // both sends inband, so people hear it
+		if (p->rtp && ast_rtp_instance_dtmf_mode_get(p->rtp) == AST_RTP_DTMF_MODE_BOTH) {
+			ast_rtp_instance_dtmf_end(p->rtp, digit);
+		} else {
+			res = -1; /* Tell Asterisk to stop inband indications */
+		}
+		break;
 	}
 	sip_pvt_unlock(p);
 
@@ -6580,6 +6607,10 @@
 		if (i->rtp) {
 			ast_rtp_instance_dtmf_mode_set(i->rtp, AST_RTP_DTMF_MODE_RFC2833);
 		}
+	} else if (ast_test_flag(&i->flags[0], SIP_DTMF) == SIP_DTMF_BOTH) {
+		if (!i->rtp || ast_rtp_instance_dtmf_mode_set(i->rtp, AST_RTP_DTMF_MODE_BOTH)) {
+			enable_dsp_detect(i);
+		}
 	}
 
 	/* Set file descriptors for audio, video, realtime text and UDPTL as needed */
@@ -6888,7 +6919,8 @@
 	}
 	/* Don't forward RFC2833 if we're not supposed to */
 	if (f && (f->frametype == AST_FRAME_DTMF_BEGIN || f->frametype == AST_FRAME_DTMF_END) &&
-	    (ast_test_flag(&p->flags[0], SIP_DTMF) != SIP_DTMF_RFC2833)) {
+	    (ast_test_flag(&p->flags[0], SIP_DTMF) != SIP_DTMF_RFC2833) &&
+	    (ast_test_flag(&p->flags[0], SIP_DTMF) != SIP_DTMF_BOTH)) {
 		ast_debug(1, "Ignoring DTMF (%c) RTP frame because dtmfmode is not RFC2833\n", f->subclass.integer);
 		return &ast_null_frame;
 	}
@@ -6917,7 +6949,8 @@
 				ast_debug(1, "Fax CNG detected on %s\n", ast->name);
 				*faxdetect = 1;
 				/* If we only needed this DSP for fax detection purposes we can just drop it now */
-				if (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_INBAND) {
+				if ((ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_INBAND) ||
+            (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_BOTH)) {
 					ast_dsp_set_features(p->dsp, DSP_FEATURE_DIGIT_DETECT);
 				} else {
 					ast_dsp_free(p->dsp);
@@ -7176,7 +7209,8 @@
 	p->capability = sip_cfg.capability;
 	p->allowtransfer = sip_cfg.allowtransfer;
 	if ((ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_RFC2833) ||
-	    (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_AUTO))
+	    (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_AUTO) ||
+	    (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_BOTH))
 		p->noncodeccapability |= AST_RTP_DTMF;
 	if (p->udptl) {
 		p->t38_maxdatagram = global_t38_maxdatagram;
@@ -14998,7 +15032,8 @@
 			p->jointcapability &= p->peercapability;
 		p->maxcallbitrate = peer->maxcallbitrate;
 		if ((ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_RFC2833) ||
-		    (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_AUTO))
+		    (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_AUTO) ||
+		    (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_BOTH))
 			p->noncodeccapability |= AST_RTP_DTMF;
 		else
 			p->noncodeccapability &= ~AST_RTP_DTMF;
@@ -15796,6 +15831,7 @@
 	{ SIP_DTMF_SHORTINFO,   "shortinfo" },
 	{ SIP_DTMF_INBAND,      "inband" },
 	{ SIP_DTMF_AUTO,        "auto" },
+	{ SIP_DTMF_BOTH,        "both" },
 	{ -1,                   NULL }, /* terminator */
 };
 
@@ -21264,7 +21300,7 @@
 		build_contact(p);			/* Build our contact header */
 
 		if (p->rtp) {
-			ast_rtp_instance_set_prop(p->rtp, AST_RTP_PROPERTY_DTMF, ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_RFC2833);
+			ast_rtp_instance_set_prop(p->rtp, AST_RTP_PROPERTY_DTMF, (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_RFC2833) || (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_BOTH));
 			ast_rtp_instance_set_prop(p->rtp, AST_RTP_PROPERTY_DTMF_COMPENSATE, ast_test_flag(&p->flags[1], SIP_PAGE2_RFC2833_COMPENSATE));
 		}
 
@@ -25227,8 +25263,10 @@
 			ast_set_flag(&flags[0], SIP_DTMF_SHORTINFO);
 		else if (!strcasecmp(v->value, "auto"))
 			ast_set_flag(&flags[0], SIP_DTMF_AUTO);
+		else if (!strcasecmp(v->value, "both"))
+			ast_set_flag(&flags[0], SIP_DTMF_BOTH);
 		else {
-			ast_log(LOG_WARNING, "Unknown dtmf mode '%s' on line %d, using rfc2833\n", v->value, v->lineno);
+			ast_log(LOG_WARNING, "Unknown dtmf mode '%s' on line %d, using NOW THERE\'S DIFFERENT TEXT HERE rfc2833\n", v->value, v->lineno);
 			ast_set_flag(&flags[0], SIP_DTMF_RFC2833);
 		}
 	} else if (!strcasecmp(v->name, "nat")) {
@@ -27645,13 +27683,18 @@
 		ast_clear_flag(&p->flags[0], SIP_DTMF);
 		ast_set_flag(&p->flags[0], SIP_DTMF_INBAND);
 		p->jointnoncodeccapability &= ~AST_RTP_DTMF;
+	} else if (!strcasecmp(mode, "both")) {
+		ast_clear_flag(&p->flags[0], SIP_DTMF);
+		ast_set_flag(&p->flags[0], SIP_DTMF_BOTH);
+		p->jointnoncodeccapability |= AST_RTP_DTMF;
 	} else {
 		ast_log(LOG_WARNING, "I don't know about this dtmf mode: %s\n", mode);
 	}
 	if (p->rtp)
-		ast_rtp_instance_set_prop(p->rtp, AST_RTP_PROPERTY_DTMF, ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_RFC2833);
+		ast_rtp_instance_set_prop(p->rtp, AST_RTP_PROPERTY_DTMF, (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_RFC2833) || (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_BOTH));
 	if ((ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_INBAND) ||
-	    (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_AUTO)) {
+	    (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_AUTO) ||
+	    (ast_test_flag(&p->flags[0], SIP_DTMF) == SIP_DTMF_BOTH)) {
 		enable_dsp_detect(p);
 	} else {
 		disable_dsp_detect(p);
diff -Naur asterisk-1.8.0/channels/sip/include/sip.h asterisk-1.8.0/channels/sip/include/sip.h
--- asterisk-1.8.0/channels/sip/include/sip.h	2010-09-15 15:22:15.000000000 -0400
+++ asterisk-1.8.0/channels/sip/include/sip.h	2010-12-11 17:56:18.000000000 -0500
@@ -19,6 +19,11 @@
  * \brief chan_sip header file
  */
 
+/*
+  This version has been kluged by Alex Fink to allow a new dtmfmode "both"
+  that recognises both rfc2833 and inband.
+*/
+
 #ifndef _SIP_H
 #define _SIP_H
 
@@ -254,6 +259,7 @@
 #define SIP_DTMF_INFO       (2 << 15) /*!< DP: DTMF Support: SIP Info messages - "info" */
 #define SIP_DTMF_AUTO       (3 << 15) /*!< DP: DTMF Support: AUTO switch between rfc2833 and in-band DTMF */
 #define SIP_DTMF_SHORTINFO  (4 << 15) /*!< DP: DTMF Support: SIP Info messages - "info" - short variant */
+#define SIP_DTMF_BOTH       (5 << 15) /*!< DP: DTMF Support: like "rfc2833" and "inband" together */
 
 /* NAT settings */
 #define SIP_NAT_FORCE_RPORT     (1 << 18) /*!< DP: Force rport even if not present in the request */
diff -Naur asterisk-1.8.0/include/asterisk/rtp_engine.h asterisk-1.8.0/include/asterisk/rtp_engine.h
--- asterisk-1.8.0/include/asterisk/rtp_engine.h	2010-10-01 22:43:45.000000000 -0400
+++ asterisk-1.8.0/include/asterisk/rtp_engine.h	2010-12-11 18:12:51.000000000 -0500
@@ -62,6 +62,10 @@
  * available for the RTP engine.
  */
 
+/*
+  This version kluged by Alex Fink to allow DTMF both ways at once.
+*/
+
 #ifndef _ASTERISK_RTP_ENGINE_H
 #define _ASTERISK_RTP_ENGINE_H
 
@@ -119,6 +123,8 @@
 	AST_RTP_DTMF_MODE_RFC2833,
 	/*! DTMF is being carried inband over the RTP stream */
 	AST_RTP_DTMF_MODE_INBAND,
+	/*! both of the above, for incoming DTMF */
+	AST_RTP_DTMF_MODE_BOTH,
 };
 
 /*! Result codes when RTP glue is queried for information */
diff -Naur asterisk-1.8.0/main/dsp.c asterisk-1.8.0/main/dsp.c
--- asterisk-1.8.0/main/dsp.c	2010-06-07 13:34:45.000000000 -0400
+++ asterisk-1.8.0/main/dsp.c	2010-12-11 17:03:45.000000000 -0500
@@ -19,6 +19,15 @@
  * at the top of the source tree.
  */
 
+/*
+ * This version is klugishly modified by Alex Fink, 2010, to recognise
+ * the US 1700 & 2200 Hz coin tone as if it were a DTMF tone.
+ *
+ * Various things below suggest that a 33ms tone with 33ms separations 
+ * might be too short to be recognised, but it seems to work okay.
+ * Does DTMF_GSIZE matter?
+ */
+
 /*! \file
  *
  * \brief Convenience Signal Processing routines
@@ -156,6 +165,7 @@
 
 #define DTMF_THRESHOLD		8.0e7
 #define FAX_THRESHOLD		8.0e7
+#define COIN_THRESHOLD		8.0e7
 #define FAX_2ND_HARMONIC	2.0     /* 4dB */
 #define DTMF_NORMAL_TWIST	6.3     /* 8dB */
 #ifdef	RADIO_RELAX
@@ -168,6 +178,7 @@
 #define DTMF_2ND_HARMONIC_ROW       (relax ? 1.7 : 2.5)     /* 4dB normal */
 #define DTMF_2ND_HARMONIC_COL	63.1    /* 18dB */
 #define DTMF_TO_TOTAL_ENERGY	42.0
+#define COIN_TO_TOTAL_ENERGY	42.0
 
 #define BELL_MF_THRESHOLD	1.6e9
 #define BELL_MF_TWIST		4.0     /* 6dB */
@@ -256,6 +267,8 @@
 {
 	goertzel_state_t row_out[4];
 	goertzel_state_t col_out[4];
+	goertzel_state_t coin_low_out;
+	goertzel_state_t coin_high_out;
 	int hits_to_begin;		/* How many successive hits needed to consider begin of a digit */
 	int misses_to_end;		/* How many successive misses needed to consider end of a digit */
 	int hits;			/* How many successive hits we have seen already */
@@ -296,10 +309,13 @@
 static const float dtmf_col[] = {
 	1209.0, 1336.0, 1477.0, 1633.0
 };
+static const float coin_low = 1700.0;
+static const float coin_high = 2200.0;
 static const float mf_tones[] = {
 	700.0, 900.0, 1100.0, 1300.0, 1500.0, 1700.0
 };
 static const char dtmf_positions[] = "123A" "456B" "789C" "*0#D";
+static const char coin_char = '$';
 static const char bell_mf_positions[] = "1247C-358A--69*---0B----#";
 static int thresholds[THRESHOLD_MAX];
 
@@ -488,6 +504,8 @@
 		goertzel_init(&s->col_out[i], dtmf_col[i], DTMF_GSIZE);
 		s->energy = 0.0;
 	}
+  goertzel_init(&s->coin_low_out, coin_low, DTMF_GSIZE);
+  goertzel_init(&s->coin_high_out, coin_high, DTMF_GSIZE);  
 	s->current_sample = 0;
 	s->hits = 0;
 	s->misses = 0;
@@ -642,6 +660,8 @@
 {
 	float row_energy[4];
 	float col_energy[4];
+  float coin_low_energy;
+  float coin_high_energy;
 	float famp;
 	int i;
 	int j;
@@ -680,6 +700,8 @@
 			goertzel_sample(s->td.dtmf.col_out + 2, amp[j]);
 			goertzel_sample(s->td.dtmf.row_out + 3, amp[j]);
 			goertzel_sample(s->td.dtmf.col_out + 3, amp[j]);
+			goertzel_sample(&s->td.dtmf.coin_low_out, amp[j]);
+			goertzel_sample(&s->td.dtmf.coin_high_out, amp[j]);
 		}
 		s->td.dtmf.current_sample += (limit - sample);
 		if (s->td.dtmf.current_sample < DTMF_GSIZE) {
@@ -701,6 +723,22 @@
 			}
 		}
 		hit = 0;
+    /* Check for the coin: test if it's past threshold and 
+       it beats all the DTMF frequency peaks.  (No twist test.) */
+    coin_low_energy = goertzel_result (&s->td.dtmf.coin_low_out);
+    coin_high_energy = goertzel_result (&s->td.dtmf.coin_high_out);
+    if (coin_low_energy >= COIN_THRESHOLD &&
+        coin_high_energy >= COIN_THRESHOLD &&
+        coin_low_energy > row_energy[best_row] &&
+        coin_high_energy > row_energy[best_row] &&
+        coin_low_energy > col_energy[best_col] &&
+        coin_high_energy > col_energy[best_col]) {
+			/* fraction of total energy test */
+			if ((coin_low_energy + coin_high_energy) > COIN_TO_TOTAL_ENERGY * s->td.dtmf.energy) {
+				/* Got a hit */
+				hit = coin_char;
+			}
+    }
 		/* Basic signal level test and the twist test */
 		if (row_energy[best_row] >= DTMF_THRESHOLD && 
 		    col_energy[best_col] >= DTMF_THRESHOLD &&
@@ -774,6 +812,8 @@
 			goertzel_reset(&s->td.dtmf.row_out[i]);
 			goertzel_reset(&s->td.dtmf.col_out[i]);
 		}
+    goertzel_reset(&s->td.dtmf.coin_low_out);
+    goertzel_reset(&s->td.dtmf.coin_high_out);
 		s->td.dtmf.energy = 0.0;
 		s->td.dtmf.current_sample = 0;
 	}