diff --git a/libs/freetdm/Makefile b/libs/freetdm/Makefile
index a8296a3334..17661180d7 100644
--- a/libs/freetdm/Makefile
+++ b/libs/freetdm/Makefile
@@ -113,7 +113,7 @@ testapp: $(SRC)/testapp.c $(MYLIB)
 	$(CC) $(INCS) -L. $(SRC)/testapp.c -o testapp -lopenzap -lm -lpthread
 
 testcid: $(SRC)/testcid.c $(MYLIB)
-	$(CC) $(INCS) -L. $(SRC)/testcid.c -o testcid -lopenzap -lm -lpthread
+	$(CC) $(INCS) -L. -g -ggdb $(SRC)/testcid.c -o testcid -lopenzap -lm -lpthread
 
 testtones: $(SRC)/testtones.c $(MYLIB)
 	$(CC) $(INCS) -L. $(SRC)/testtones.c -o testtones -lopenzap -lm -lpthread
diff --git a/libs/freetdm/src/fsk.c b/libs/freetdm/src/fsk.c
index 69b2edfc88..d933166227 100644
--- a/libs/freetdm/src/fsk.c
+++ b/libs/freetdm/src/fsk.c
@@ -46,7 +46,7 @@
 #define M_PI        3.14159265358979323846
 #endif
 
-static fsk_modem_definition_t fsk_modem_definitions[] =
+fsk_modem_definition_t fsk_modem_definitions[] =
 {
     { /* FSK_V23_FORWARD_MODE1	*/	1700,	1300,	600		},
     { /* FSK_V23_FORWARD_MODE2	*/	2100,	1300,	1200	},
diff --git a/libs/freetdm/src/include/fsk.h b/libs/freetdm/src/include/fsk.h
index e6ca995d57..b098444d03 100644
--- a/libs/freetdm/src/include/fsk.h
+++ b/libs/freetdm/src/include/fsk.h
@@ -107,5 +107,7 @@ void					dsp_fsk_destroy(dsp_fsk_handle_t **handle);
 
 void					dsp_fsk_sample(dsp_fsk_handle_t *handle, double normalized_sample);
 
+extern fsk_modem_definition_t fsk_modem_definitions[];
+
 #endif	
 
diff --git a/libs/freetdm/src/include/libteletone_generate.h b/libs/freetdm/src/include/libteletone_generate.h
index 177c893966..de6697bb29 100644
--- a/libs/freetdm/src/include/libteletone_generate.h
+++ b/libs/freetdm/src/include/libteletone_generate.h
@@ -156,7 +156,6 @@ static __inline__ int16_t teletone_dds_state_modulate_sample(teletone_dds_state_
 	}
 
 	dds->phase_accumulator += dds->phase_rate[pindex];
-
     return (int16_t) (sample * dds->scale_factor >> 15);
 }
 
diff --git a/libs/freetdm/src/include/openzap.h b/libs/freetdm/src/include/openzap.h
index e1dc74c649..0e7887bd20 100644
--- a/libs/freetdm/src/include/openzap.h
+++ b/libs/freetdm/src/include/openzap.h
@@ -241,6 +241,46 @@ static __inline__ char *zap_clean_string(char *s)
 	return s;
 }
 
+struct zap_bitstream {
+	uint8_t *data;
+	uint32_t datalen;
+	uint32_t byte_index;
+	uint8_t bit_index;
+	int8_t endian;
+	uint8_t top;
+	uint8_t bot;
+	uint8_t ss;
+	uint8_t ssv;
+};
+
+struct zap_fsk_data_state {
+	dsp_fsk_handle_t *fsk1200_handle;
+	uint8_t init;
+	uint8_t *buf;
+	size_t bufsize;
+	zap_size_t blen;
+	zap_size_t bpos;
+	zap_size_t dlen;
+	zap_size_t ppos;
+	int checksum;
+};
+
+struct zap_fsk_modulator {
+	teletone_dds_state_t dds;
+	zap_bitstream_t bs;
+	uint32_t carrier_bits_start;
+	uint32_t carrier_bits_stop;
+	uint32_t chan_sieze_bits;
+	uint32_t bit_factor;
+	uint32_t bit_accum;
+	uint32_t sample_counter;
+	fsk_modem_types_t modem_type;
+	zap_fsk_data_state_t *fsk_data;
+	zap_fsk_write_sample_t write_sample_callback;
+	void *user_data;
+	int16_t sample_buffer[64];
+};
+
 struct zap_caller_data {
 	char cid_name[80];
 	char cid_num[80];
@@ -364,11 +404,31 @@ struct zap_io_interface {
 	zio_span_next_event_t next_event;
 };
 
+#define zap_fsk_modulator_send_all(_it) zap_fsk_modulator_generate_chan_sieze(_it); \
+	zap_fsk_modulator_generate_carrier_bits(_it, _it->carrier_bits_start); \
+	zap_fsk_modulator_send_data(_it); \
+	zap_fsk_modulator_generate_carrier_bits(_it, _it->carrier_bits_stop)
+
+zap_status_t zap_fsk_modulator_init(zap_fsk_modulator_t *fsk_trans,
+									fsk_modem_types_t modem_type,
+									uint32_t sample_rate,
+									zap_fsk_data_state_t *fsk_data,
+									float db_level,
+									uint32_t carrier_bits_start,
+									uint32_t carrier_bits_stop,
+									uint32_t chan_sieze_bits,
+									zap_fsk_write_sample_t write_sample_callback,
+									void *user_data);
+int8_t zap_bitstream_get_bit(zap_bitstream_t *bsp);
+void zap_bitstream_init(zap_bitstream_t *bsp, uint8_t *data, uint32_t datalen, zap_endian_t endian, int ss);
 zap_status_t zap_fsk_data_parse(zap_fsk_data_state_t *state, zap_size_t *type, char **data, zap_size_t *len);
 zap_status_t zap_fsk_demod_feed(zap_fsk_data_state_t *state, int16_t *data, size_t samples);
 zap_status_t zap_fsk_demod_destroy(zap_fsk_data_state_t *state);
 int zap_fsk_demod_init(zap_fsk_data_state_t *state, int rate, uint8_t *buf, size_t bufsize);
-
+zap_status_t zap_fsk_data_init(zap_fsk_data_state_t *state, uint8_t *data, uint32_t datalen);
+zap_status_t zap_fsk_data_add_mdmf(zap_fsk_data_state_t *state, zap_mdmf_type_t type, int8_t *data, uint32_t datalen);
+zap_status_t zap_fsk_data_add_checksum(zap_fsk_data_state_t *state);
+zap_status_t zap_fsk_data_add_sdmf(zap_fsk_data_state_t *state, char *date, char *number);
 zap_status_t zap_channel_outgoing_call(zap_channel_t *zchan);
 void zap_channel_rotate_tokens(zap_channel_t *zchan);
 void zap_channel_clear_detected_tones(zap_channel_t *zchan);
@@ -403,7 +463,7 @@ zap_status_t zap_global_destroy(void);
 void zap_global_set_logger(zap_logger_t logger);
 void zap_global_set_default_logger(int level);
 uint32_t zap_separate_string(char *buf, char delim, char **array, int arraylen);
-void print_bits(uint8_t *b, int bl, char *buf, int blen, int e);
+void print_bits(uint8_t *b, int bl, char *buf, int blen, int e, int ss);
 ZIO_CODEC_FUNCTION(zio_slin2ulaw);
 ZIO_CODEC_FUNCTION(zio_ulaw2slin);
 ZIO_CODEC_FUNCTION(zio_slin2alaw);
diff --git a/libs/freetdm/src/include/zap_types.h b/libs/freetdm/src/include/zap_types.h
index 84f74ee556..2ae6e7b05d 100644
--- a/libs/freetdm/src/include/zap_types.h
+++ b/libs/freetdm/src/include/zap_types.h
@@ -60,9 +60,15 @@ struct zap_io_interface;
 
 #define ZAP_COMMAND_OBJ_INT *((int *)obj)
 #define ZAP_COMMAND_OBJ_CHAR_P (char *)obj
+#define ZAP_FSK_MOD_FACTOR 0x10000
 
 typedef uint64_t zap_time_t; 
 
+typedef enum {
+	ZAP_ENDIAN_BIG = 1,
+	ZAP_ENDIAN_LITTLE = -1
+} zap_endian_t;
+
 typedef enum {
 	ZAP_CID_TYPE_SDMF = 0x04,
 	ZAP_CID_TYPE_MDMF = 0x80
@@ -75,28 +81,12 @@ typedef enum {
 	MDMF_NO_NUM = 4,
 	MDMF_PHONE_NAME = 7,
 	MDMF_NO_NAME = 8,
-	MDMF_INVALID = 9
+	MDMF_ALT_ROUTE = 9,
+	MDMF_INVALID = 10
 } zap_mdmf_type_t;
-#define MDMF_STRINGS "X", "DATETIME", "PHONE_NUM", "DDN", "NO_NUM", "X", "X", "PHONE_NAME", "NO_NAME", "INVALID"
+#define MDMF_STRINGS "X", "DATETIME", "PHONE_NUM", "DDN", "NO_NUM", "X", "X", "PHONE_NAME", "NO_NAME", "ALT_ROUTE", "INVALID"
 ZAP_STR2ENUM_P(zap_str2zap_mdmf_type, zap_mdmf_type2str, zap_mdmf_type_t)
 
-struct zap_fsk_data_state {
-	dsp_fsk_handle_t *fsk1200_handle;
-	uint8_t init;
-	uint8_t *buf;
-	size_t bufsize;
-	zap_size_t blen;
-	zap_size_t bpos;
-	zap_size_t dlen;
-	zap_size_t ppos;
-	int checksum;
-};
-typedef struct zap_fsk_data_state zap_fsk_data_state_t;
-
-typedef int (*zap_fsk_data_decoder_t)(zap_fsk_data_state_t *state);
-
-
-
 #define ZAP_TONEMAP_LEN 128
 typedef enum {
 	ZAP_TONEMAP_NONE,
@@ -364,13 +354,18 @@ typedef zap_status_t (*zio_write_t) ZIO_WRITE_ARGS ;
 #define ZAP_LOG_ALERT ZAP_PRE, ZAP_LOG_LEVEL_ALERT
 #define ZAP_LOG_EMERG ZAP_PRE, ZAP_LOG_LEVEL_EMERG
 
-
+typedef struct zap_fsk_data_state zap_fsk_data_state_t;
+typedef int (*zap_fsk_data_decoder_t)(zap_fsk_data_state_t *state);
+typedef zap_status_t (*zap_fsk_write_sample_t)(int16_t *buf, zap_size_t buflen, void *user_data);
 typedef void (*zap_logger_t)(char *file, const char *func, int line, int level, char *fmt, ...);
 typedef struct zap_io_interface zap_io_interface_t;
 typedef struct hashtable zap_hash_t;
 typedef struct hashtable_itr zap_hash_itr_t;
 typedef struct key zap_hash_key_t;
 typedef struct value zap_hash_val_t;
+typedef struct zap_bitstream zap_bitstream_t;
+typedef struct zap_fsk_modulator zap_fsk_modulator_t;
+
 #endif
 
 /* For Emacs:
diff --git a/libs/freetdm/src/testcid.c b/libs/freetdm/src/testcid.c
index 545794689c..a75dee81de 100644
--- a/libs/freetdm/src/testcid.c
+++ b/libs/freetdm/src/testcid.c
@@ -1,17 +1,73 @@
 #include "openzap.h"
 
+struct helper {
+	int fd;
+};
+
+zap_status_t my_write_sample(int16_t *buf, zap_size_t buflen, void *user_data)
+{
+	int x ;
+
+	struct helper *foo = (struct helper *) user_data;
+	for (x = 0; x < buflen; x++) {
+		printf("%x ", buf[x]);
+	}
+	printf("\n");
+	write(foo->fd, buf, buflen * 2);
+}
+
 int main(int argc, char *argv[])
 {
-	zap_fsk_data_state_t state = {0};
-	int fd;
+	struct zap_fsk_modulator fsk_trans;
+	zap_fsk_data_state_t fsk_data = {0};
+	int fd = -1;
 	int16_t buf[160] = {0};
 	ssize_t len = 0;
 	int type, mlen;
 	char *sp;
 	char str[128] = "";
 	char fbuf[256];
+	uint8_t databuf[1024] = "";
+	struct helper foo;
+	
+	
+	
+	if (argc < 2) {
+		int x;
+		char *url = "sip:cool@rad.com";
 
-	if (argc < 2 || zap_fsk_demod_init(&state, 8000, fbuf, sizeof(fbuf))) {
+		if ((fd = open("tone.raw", O_WRONLY | O_TRUNC | O_CREAT, S_IRUSR | S_IWUSR)) < 0) {
+			fprintf(stderr, "File Error!\n", strerror(errno));
+			exit(-1);
+		}
+
+
+		zap_fsk_data_init(&fsk_data, databuf, sizeof(databuf));
+#if 1
+		zap_fsk_data_add_mdmf(&fsk_data, MDMF_DATETIME, "06061234", 8);
+		zap_fsk_data_add_mdmf(&fsk_data, MDMF_PHONE_NUM, "5551212", 7);
+		zap_fsk_data_add_mdmf(&fsk_data, MDMF_PHONE_NAME, "Fred Smith", 10);
+		//zap_fsk_data_add_mdmf(&fsk_data, MDMF_ALT_ROUTE, url, strlen(url));
+#else
+		zap_fsk_data_add_sdmf(&fsk_data, "06061234", "0");
+		//zap_fsk_data_add_sdmf(&state, "06061234", "5551212");
+#endif
+		zap_fsk_data_add_checksum(&fsk_data);
+
+		foo.fd = fd;
+
+
+		zap_fsk_modulator_init(&fsk_trans, FSK_BELL202, 8000, &fsk_data, -14, 180, 5, 300, my_write_sample, &foo);
+		zap_fsk_modulator_send_all((&fsk_trans));
+
+		if (fd > -1) {
+			close (fd);
+		}
+
+		return 0;
+	}
+
+	if (zap_fsk_demod_init(&fsk_data, 8000, fbuf, sizeof(fbuf))) {
 		printf("wtf\n");
 		return 0;
 	}
@@ -22,19 +78,19 @@ int main(int argc, char *argv[])
 	}
 
 	while((len = read(fd, buf, sizeof(buf))) > 0) {
-		if (zap_fsk_demod_feed(&state, buf, len / 2) != ZAP_SUCCESS) {
+		if (zap_fsk_demod_feed(&fsk_data, buf, len / 2) != ZAP_SUCCESS) {
 			break;
 		}
 	}
 
-	while(zap_fsk_data_parse(&state, &type, &sp, &mlen) == ZAP_SUCCESS) {
+	while(zap_fsk_data_parse(&fsk_data, &type, &sp, &mlen) == ZAP_SUCCESS) {
 		zap_copy_string(str, sp, mlen+1);
 		*(str+mlen) = '\0';
 		zap_clean_string(str);
 		printf("TYPE %d (%s) LEN %d VAL [%s]\n", type, zap_mdmf_type2str(type), mlen, str);
 	}
 
-	zap_fsk_demod_destroy(&state);
+	zap_fsk_demod_destroy(&fsk_data);
 
 	close(fd);
 }
diff --git a/libs/freetdm/src/zap_callerid.c b/libs/freetdm/src/zap_callerid.c
index f3a685f55a..7b41117670 100644
--- a/libs/freetdm/src/zap_callerid.c
+++ b/libs/freetdm/src/zap_callerid.c
@@ -3,6 +3,7 @@
 #include "uart.h"
 
 
+
 static void fsk_byte_handler (void *x, int data)
 {
 	zap_fsk_data_state_t *state = (zap_fsk_data_state_t *) x;
@@ -36,6 +37,62 @@ static void fsk_byte_handler (void *x, int data)
 	}
 }
 
+zap_status_t zap_fsk_data_init(zap_fsk_data_state_t *state, uint8_t *data, uint32_t datalen)
+{
+	memset(state, 0, sizeof(*state));
+	state->buf = data;
+	state->bufsize = datalen;
+	state->bpos = 2;
+
+	return ZAP_SUCCESS;
+}
+
+zap_status_t zap_fsk_data_add_sdmf(zap_fsk_data_state_t *state, char *date, char *number)
+{
+	size_t dlen = strlen(date);
+	size_t nlen = strlen(number);
+
+	state->buf[0] = ZAP_CID_TYPE_SDMF;
+	memcpy(&state->buf[state->bpos], date, dlen);
+	state->bpos += dlen;
+	memcpy(&state->buf[state->bpos], number, nlen);
+	state->bpos += nlen;
+
+	return ZAP_SUCCESS;
+}
+
+zap_status_t zap_fsk_data_add_mdmf(zap_fsk_data_state_t *state, zap_mdmf_type_t type, int8_t *data, uint32_t datalen)
+{
+	state->buf[0] = ZAP_CID_TYPE_MDMF;
+	state->buf[state->bpos++] = type;
+	state->buf[state->bpos++] = datalen;
+	memcpy(&state->buf[state->bpos], data, datalen);
+	state->bpos += datalen;
+	return ZAP_SUCCESS;
+}
+
+
+zap_status_t zap_fsk_data_add_checksum(zap_fsk_data_state_t *state)
+{
+	uint32_t i;
+	uint8_t check = 0;
+
+	state->buf[1] = state->bpos - 2;
+
+	for (i = 0; i < state->bpos; i++) {
+		check += state->buf[i];
+	}
+
+	state->checksum = state->buf[state->bpos] = 256 - check;
+	state->bpos++;
+
+	state->dlen = state->bpos;
+	state->blen = state->buf[1];
+
+	return ZAP_SUCCESS;
+}
+
+
 zap_status_t zap_fsk_data_parse(zap_fsk_data_state_t *state, zap_size_t *type, char **data, zap_size_t *len)
 {
 
@@ -54,6 +111,7 @@ zap_status_t zap_fsk_data_parse(zap_fsk_data_state_t *state, zap_size_t *type, c
 		}
 		state->checksum = sum % 256;
 		state->ppos = 2;		
+
 		if (state->buf[0] != ZAP_CID_TYPE_MDMF && state->buf[0] != ZAP_CID_TYPE_SDMF) {
 			state->checksum = -1;
 		}
@@ -139,4 +197,101 @@ int zap_fsk_demod_init(zap_fsk_data_state_t *state, int rate, uint8_t *buf, zap_
 	return ZAP_SUCCESS;
 }
 
+zap_size_t zap_fsk_modulator_generate_bit(zap_fsk_modulator_t *fsk_trans, int8_t bit, int16_t *buf, zap_size_t buflen)
+{
+	zap_size_t i;
+		
+	for(i = 0 ; i < buflen; i++) {
+		fsk_trans->bit_accum += fsk_trans->bit_factor;
+		if (fsk_trans->bit_accum >= ZAP_FSK_MOD_FACTOR) {
+			fsk_trans->bit_accum -= (ZAP_FSK_MOD_FACTOR + fsk_trans->bit_factor);
+			break;
+		}
+
+		buf[i] = teletone_dds_state_modulate_sample(&fsk_trans->dds, bit);
+	}
+
+	return i;
+}
+
+
+int32_t zap_fsk_modulator_generate_carrier_bits(zap_fsk_modulator_t *fsk_trans, uint32_t bits)
+{
+	uint32_t i = 0;
+	zap_size_t r = 0;
+	int bit = 1;
+
+	for (i = 0; i < bits; i++) {
+		if ((r = zap_fsk_modulator_generate_bit(fsk_trans, bit, fsk_trans->sample_buffer, sizeof(fsk_trans->sample_buffer) / 2))) {
+			fsk_trans->write_sample_callback(fsk_trans->sample_buffer, r, fsk_trans->user_data);
+		} else {
+			break;
+		}
+	}
+
+	return i;
+}
+
+
+void zap_fsk_modulator_generate_chan_sieze(zap_fsk_modulator_t *fsk_trans)
+{
+	uint32_t i = 0;
+	zap_size_t r = 0;
+	int bit = 0;
+	
+	for (i = 0; i < fsk_trans->chan_sieze_bits; i++) {
+		if ((r = zap_fsk_modulator_generate_bit(fsk_trans, bit, fsk_trans->sample_buffer, sizeof(fsk_trans->sample_buffer) / 2))) {
+			fsk_trans->write_sample_callback(fsk_trans->sample_buffer, r, fsk_trans->user_data);
+		} else {
+			break;
+		}
+		bit = !bit;
+	}
+	
+
+}
+
+
+void zap_fsk_modulator_send_data(zap_fsk_modulator_t *fsk_trans)
+{
+	zap_size_t r = 0;
+	int8_t bit = 0;
+
+	while((bit = zap_bitstream_get_bit(&fsk_trans->bs)) > -1) {
+		if ((r = zap_fsk_modulator_generate_bit(fsk_trans, bit, fsk_trans->sample_buffer, sizeof(fsk_trans->sample_buffer) / 2))) {
+			fsk_trans->write_sample_callback(fsk_trans->sample_buffer, r, fsk_trans->user_data);
+		} else {
+			break;
+		}
+	}
+}
+
+
+zap_status_t zap_fsk_modulator_init(zap_fsk_modulator_t *fsk_trans,
+									fsk_modem_types_t modem_type,
+									uint32_t sample_rate,
+									zap_fsk_data_state_t *fsk_data,
+									float db_level,
+									uint32_t carrier_bits_start,
+									uint32_t carrier_bits_stop,
+									uint32_t chan_sieze_bits,
+									zap_fsk_write_sample_t write_sample_callback,
+									void *user_data)
+{
+	memset(fsk_trans, 0, sizeof(*fsk_trans));
+	fsk_trans->modem_type = modem_type;
+	teletone_dds_state_set_tone(&fsk_trans->dds, fsk_modem_definitions[fsk_trans->modem_type].freq_space, sample_rate, 0);
+	teletone_dds_state_set_tone(&fsk_trans->dds, fsk_modem_definitions[fsk_trans->modem_type].freq_mark, sample_rate, 1);
+	fsk_trans->bit_factor = (fsk_modem_definitions[fsk_trans->modem_type].baud_rate * ZAP_FSK_MOD_FACTOR) / (float)sample_rate;
+	fsk_trans->bit_accum = 0;
+	fsk_trans->fsk_data = fsk_data;
+	teletone_dds_state_set_tx_level(&fsk_trans->dds, db_level);
+	zap_bitstream_init(&fsk_trans->bs, fsk_trans->fsk_data->buf, fsk_trans->fsk_data->dlen, ZAP_ENDIAN_BIG, 1);
+	fsk_trans->carrier_bits_start = carrier_bits_start;
+	fsk_trans->carrier_bits_stop = carrier_bits_stop;
+	fsk_trans->chan_sieze_bits = chan_sieze_bits;
+	fsk_trans->write_sample_callback = write_sample_callback;
+	fsk_trans->user_data = user_data;
+	return ZAP_SUCCESS;
+}
 
diff --git a/libs/freetdm/src/zap_io.c b/libs/freetdm/src/zap_io.c
index d4df53f3ce..597979c231 100644
--- a/libs/freetdm/src/zap_io.c
+++ b/libs/freetdm/src/zap_io.c
@@ -1832,34 +1832,95 @@ uint32_t zap_separate_string(char *buf, char delim, char **array, int arraylen)
 	return argc;
 }
 
-void print_bits(uint8_t *b, int bl, char *buf, int blen, int e)
+void zap_bitstream_init(zap_bitstream_t *bsp, uint8_t *data, uint32_t datalen, zap_endian_t endian, int ss)
 {
-	int i,j = 0, k, l = 0;
+	memset(bsp, 0, sizeof(*bsp));
+	bsp->data = data;
+	bsp->datalen = datalen;
+	bsp->endian = endian;
+	bsp->ss = ss;
+	
+	if (endian < 0) {
+		bsp->top = bsp->bit_index = 7;
+		bsp->bot = 0;
+	} else {
+		bsp->top = bsp->bit_index = 0;
+		bsp->bot = 7;
+	}
+
+}
+
+int8_t zap_bitstream_get_bit(zap_bitstream_t *bsp)
+{
+	int8_t bit = -1;
+	
+
+	if (bsp->byte_index >= bsp->datalen) {
+		goto done;
+	}
+
+	if (bsp->ss) {
+		if (!bsp->ssv) {
+			bsp->ssv = 1;
+			return 0;
+		} else if (bsp->ssv == 2) {
+			bsp->byte_index++;
+			bsp->ssv = 0;
+			return 1;
+		}
+	}
+
+
+
+
+	bit = (bsp->data[bsp->byte_index] >> (bsp->bit_index)) & 1;
+	
+	if (bsp->bit_index == bsp->bot) {
+		bsp->bit_index = bsp->top;
+		if (bsp->ss) {
+			bsp->ssv = 2;
+			goto done;
+		} 
+
+		if (++bsp->byte_index > bsp->datalen) {
+			bit = -1;
+			goto done;
+		}
+		
+	} else {
+		bsp->bit_index += bsp->endian;
+	}
+
+
+ done:
+	return bit;
+}
+
+
+void print_bits(uint8_t *b, int bl, char *buf, int blen, zap_endian_t e, int ss)
+{
+	zap_bitstream_t bs;
+	int j = 0, c = 0;
+	int8_t bit;
+	uint32_t last;
 
 	if (blen < (bl * 10) + 2) {
-		return;
-	}
-
-	for (k = 0 ; k < bl; k++) {
-		buf[j++] = '[';
-		if (e) {
-			for(i = 7; i >= 0; i--) {
-				buf[j++] = ((b[k] & (1 << i)) ? '1' : '0');
-			}
-		} else {
-			for(i = 0; i < 8; i++) {
-				buf[j++] = ((b[k] & (1 << i)) ? '1' : '0');
-			}
-		}
-		buf[j++] = ']';
-		buf[j++] = ' ';
-		if (++l == 6) {
-			buf[j++] = '\n';
-			l = 0;
-		}
-	}
+        return;
+    }
 	
-	buf[j++] = '\0';
+	zap_bitstream_init(&bs, b, bl, e, ss);
+	last = bs.byte_index;	
+	while((bit = zap_bitstream_get_bit(&bs)) > -1) {
+		buf[j++] = bit ? '1' : '0';
+		if (bs.byte_index != last) {
+			buf[j++] = ' ';
+			last = bs.byte_index;
+			if (++c == 8) {
+				buf[j++] = '\n';
+				c = 0;
+			}
+		}
+	}
 
 }
 
diff --git a/libs/freetdm/src/zap_isdn.c b/libs/freetdm/src/zap_isdn.c
index 76ad83ca25..f9577e4798 100644
--- a/libs/freetdm/src/zap_isdn.c
+++ b/libs/freetdm/src/zap_isdn.c
@@ -89,7 +89,7 @@ static int zap_isdn_921_21(void *pvt, L2UCHAR *msg, L2INT mlen)
 	zap_size_t len = (zap_size_t) mlen;
 #ifdef IODEBUG
 	char bb[4096] = "";
-	print_bits(msg, (int)len, bb, sizeof(bb), 1);
+	print_bits(msg, (int)len, bb, sizeof(bb), 1, 0);
 	zap_log(ZAP_LOG_DEBUG, "WRITE %d\n%s\n%s\n\n", (int)len, LINE, bb);
 
 #endif
@@ -140,7 +140,7 @@ static void *zap_isdn_run(zap_thread_t *me, void *obj)
 					if (zap_channel_read(data->dchan, buf, &len) == ZAP_SUCCESS) {
 #ifdef IODEBUG
 						char bb[4096] = "";
-						print_bits(buf, (int)len, bb, sizeof(bb), 1);
+						print_bits(buf, (int)len, bb, sizeof(bb), 1, 0);
 						zap_log(ZAP_LOG_DEBUG, "READ %d\n%s\n%s\n\n", (int)len, LINE, bb);
 #endif