diff --git a/src/pstn/main.c b/src/pstn/main.c
index 15e6c12..7605363 100644
--- a/src/pstn/main.c
+++ b/src/pstn/main.c
@@ -104,6 +104,12 @@ static void print_help()
 	printf("        Enable en-block dialing, to collect number before setup. The value\n");
 	printf("        given is the number of seconds to wait for more digits to be dialed.\n");
 	printf("        (default = %d)\n", enblock);
+	printf(" -D --dial-hint xxxx | xxxx-yyyy\n");
+	printf("        The given one or multpiple hits for numbers with a fixed length. This\n");
+	printf("        can be a single number or a range of number. If a range is given, xxxx\n");
+	printf("        and yyyy must have equal length. If one of the given numbers are dialed,\n");
+	printf("        the en-block dialing is complete and there is no need to wait for the\n");
+	printf("        timeout.\n");
 	printf(" --recall\n");
 	printf("        Enable recall / call waiting. (disabled by default)\n");
 	printf(" -R --ringing-type-incoming <type>\n");
@@ -166,6 +172,7 @@ static void add_options(void)
 	option_add(OPT_TX_CID_BELL, "cid-bell", 0);
 	option_add(OPT_TX_CID_DTMF, "cid-dtmf", 1);
 	option_add(OPT_TX_ENBLOCK, "enblock", 1);
+	option_add('D', "dial-hint", 1);
 	option_add(OPT_TX_RECALL, "recall", 0);
 	option_add(OPT_TX_RING_I, "ringing-type-incoming", 1);
 	option_add(OPT_TX_RING_H, "ringing-type-hold", 1);
@@ -245,6 +252,13 @@ static int handle_options(int short_option, int argi, char **argv)
 	case OPT_TX_RECALL:
 		recall = 1;
 		break;
+	case 'D':
+		rc = add_dial_hint(argv[argi]);
+		if (rc < 0) {
+			fprintf(stderr, "Given dial hint '%s' is not valid, please use -h for help.\n", argv[argi]);
+			return rc;
+		}
+		break;
 	case OPT_TX_RING_I:
 		if (ringing_type_incoming_num == SUBSCRIBER_MAX) {
 			fprintf(stderr, "Cannot define more than %d ringing types.\n", SUBSCRIBER_MAX);
@@ -425,6 +439,8 @@ error:
 		pstn_destroy(pstn_ep);
 	}
 
+	purge_dial_hints();
+
 	options_free();
 
 	/* exit fm */
diff --git a/src/pstn/pstn.c b/src/pstn/pstn.c
index 52e4263..bc93f80 100644
--- a/src/pstn/pstn.c
+++ b/src/pstn/pstn.c
@@ -159,6 +159,112 @@ static const char *timer_ident_name(enum timer_ident ident)
 	}
 };
 
+/*
+ * dial hints
+ */
+
+static struct dial_hint *dial_hints = NULL;
+
+int add_dial_hint(const char *arg)
+{
+	struct dial_hint *hint;
+	int i, dash;
+
+	hint = calloc(1, sizeof(*hint));
+	if (!hint)
+		return -ENOMEM;
+
+	for (i = 0, dash = -1; arg[i]; i++) {
+		if (arg[i] == '-') {
+			/* only single dash is allowed */
+			if (dash >= 0)
+				goto error;
+			dash = i;
+			continue;
+		}
+		/* only digits 0..9 are allowd */
+		if (arg[i] < '0' || arg[i] > '9')
+			goto error;
+	}
+
+	if (dash < 0) {
+		/* number must have at least one digit */
+		if (i < 1)
+			goto error;
+		hint->length = i;
+		hint->from = calloc(1, i + 1);
+		if (!hint->from)
+			goto error;
+		strcpy(hint->from, arg);
+		PDEBUG(DTEL, DEBUG_INFO, "Added dial hint '%s'\n", hint->from);
+	} else {
+		/* both numbers must have same lenth */
+		if (dash != i - dash - 1)
+			goto error;
+		/* there must be digits at all */
+		if (dash < 1)
+			goto error;
+		hint->length = dash;
+		hint->from = calloc(1, dash + 1);
+		if (!hint->from)
+			goto error;
+		strncpy(hint->from, arg, dash);
+		hint->to = calloc(1, dash + 1);
+		if (!hint->to)
+			goto error;
+		strcpy(hint->to, arg + dash + 1);
+		/* second string must be greater than first string */
+		if (strcmp(hint->from, hint->to) > 0)
+			goto error;
+		PDEBUG(DTEL, DEBUG_INFO, "Added dial hint '%s' - '%s'\n", hint->from, hint->to);
+	}
+
+	hint->next = dial_hints;
+	dial_hints = hint;
+
+	return 0;
+
+error:
+	free(hint->from);
+	free(hint->to);
+	free(hint);
+
+	return -EINVAL;
+}
+
+static int check_dial_hint(const char *number)
+{
+	struct dial_hint *hint;
+	size_t length = strlen(number);
+
+	for (hint = dial_hints; hint; hint = hint->next) {
+		if (hint->length != length)
+			continue;
+		if (hint->from && !hint->to) {
+			if (strncmp(number, hint->from, hint->length) == 0)
+				return 1;
+		}
+		if (hint->from && hint->to) {
+			if (strncmp(number, hint->from, hint->length) >= 0
+			 && strncmp(number, hint->to, hint->length) <= 0)
+				return 1;
+		}
+	}
+	return 0;
+}
+
+void purge_dial_hints(void)
+{
+	struct dial_hint *hint;
+
+	while ((hint = dial_hints)) {
+		dial_hints = hint->next;
+		free(hint->from);
+		free(hint->to);
+		free(hint);
+	}
+}
+
 /*
  * Endpoint instance
  */
@@ -521,7 +627,7 @@ void recv_dtmf(void *priv, char digit, dtmf_meas_t __attribute__((unused)) *meas
 	/* if we are receiving digits en block */
 	if (pstn->call[PSTN_CALL_ACTIVE]->state == CALL_STATE_ENBLOCK) {
 		if (digit == '#') {
-			PDEBUG(DTEL, DEBUG_DEBUG, "Number is complete, send setup\n");
+			PDEBUG(DTEL, DEBUG_DEBUG, "Digit '#' received, number is complete, send setup\n");
 			/* setup (en block) */
 			setup_ind(pstn, PSTN_CALL_ACTIVE, pstn->dialing, 1);
 			return;
@@ -531,6 +637,12 @@ void recv_dtmf(void *priv, char digit, dtmf_meas_t __attribute__((unused)) *meas
 		char called[2] = { digit, '\0' };
 		strncat(pstn->dialing, called, sizeof(pstn->dialing) - 1);
 		PDEBUG(DTEL, DEBUG_DEBUG, "Appending digit, so dial string is now: '%s'.\n", pstn->dialing);
+		if (check_dial_hint(pstn->dialing)) {
+			PDEBUG(DTEL, DEBUG_DEBUG, "Number in list of dial hints received, number is complete, send setup\n");
+			/* setup (en block) */
+			setup_ind(pstn, PSTN_CALL_ACTIVE, pstn->dialing, 1);
+			return;
+		}
 		/* start dial timer */
 		timer_on(pstn, (double)pstn->enblock, TIMER_IDENT_DIALING);
 		return;
@@ -1492,6 +1604,12 @@ static void v5_sig_ind(pstn_t *pstn, uint8_t *data, int len)
 			/* append digit */
 			strncat(pstn->dialing, called, sizeof(pstn->dialing) - 1);
 			PDEBUG(DTEL, DEBUG_DEBUG, "Appending digit, so dial string is now: '%s'.\n", pstn->dialing);
+			if (check_dial_hint(pstn->dialing)) {
+				PDEBUG(DTEL, DEBUG_DEBUG, "Number in list of dial hints received, number is complete, send setup\n");
+				/* setup (en block) */
+				setup_ind(pstn, PSTN_CALL_ACTIVE, pstn->dialing, 1);
+				break;
+			}
 			/* start dial timer */
 			timer_on(pstn, (double)pstn->enblock, TIMER_IDENT_DIALING);
 			break;
diff --git a/src/pstn/pstn.h b/src/pstn/pstn.h
index 4107328..a1fd35b 100644
--- a/src/pstn/pstn.h
+++ b/src/pstn/pstn.h
@@ -104,6 +104,12 @@ struct call {
 	int			on_hold;		/* track hold/retrieval notification */
 };
 
+struct dial_hint {
+	struct dial_hint	*next;
+	size_t			length;
+	char			*from, *to;
+};
+
 typedef struct pstn {
 	osmo_cc_endpoint_t	cc_ep;
 
@@ -119,6 +125,7 @@ typedef struct pstn {
 	int			cid_bell;		/* use V.23 or Bell 202 FSK tones */
 	int			cid_dtmf;		/* use DTMF instead of FSK caller ID */
 	int			enblock;		/* receive digits before transmitting them via SETUP message (timeout as given) */
+	struct dial_hint	dial_hints;		/* list of numbers that are complete */
 	int			recall;			/* support recall / waiting call */
 	int			*ringing_types_incoming;/* cadenced rining on incoming call */
 	int			ringing_type_hold;	/* cadenced rining on waiting call */
@@ -153,9 +160,10 @@ typedef struct pstn {
         int			tx_buffer_pos;		/* current position in transmit audio buffer */
 } pstn_t;
 
+int add_dial_hint(const char *arg);
+void purge_dial_hints(void);
 void pstn_destroy(pstn_t *pstn_ep);
 pstn_t *pstn_create(void);
 int pstn_init(pstn_t *pstn, const char *name, const char *socketname, const char **subscribers, int subscriber_num, uint8_t serving_location, int tx_delay, enum pstn_cid_method clip, int cid_bell, int cid_dtmf, int clip_date, int enblock, int recall, int *ringing_types_incoming, int ringing_type_hold, enum tones_type tones_type, char law);
 void cc_message(osmo_cc_endpoint_t *ep, uint32_t callref, osmo_cc_msg_t *msg);
 void rtp_work(pstn_t *pstn_ep);
-