diff --git a/openbsc/include/openbsc/gsm_data.h b/openbsc/include/openbsc/gsm_data.h
index 9bddd7a..52c6a03 100644
--- a/openbsc/include/openbsc/gsm_data.h
+++ b/openbsc/include/openbsc/gsm_data.h
@@ -60,6 +60,7 @@
 #include <openbsc/abis_rsl.h>
 #include <openbsc/mncc.h>
 #include <openbsc/tlv.h>
+#include <openbsc/bitvec.h>
 
 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
 
@@ -381,6 +382,13 @@
 		struct gsm48_cell_sel_par cell_sel_par;
 		struct gsm48_cell_options cell_options;
 		struct gsm48_control_channel_descr chan_desc;
+		struct bitvec neigh_list;
+		struct bitvec cell_alloc;
+		struct {
+			/* bitmask large enough for all possible ARFCN's */
+			u_int8_t neigh_list[1024/8];
+			u_int8_t cell_alloc[1024/8];
+		} data;
 	} si_common;
 
 	/* ip.accesss Unit ID's have Site/BTS/TRX layout */
diff --git a/openbsc/src/gsm_data.c b/openbsc/src/gsm_data.c
index cdaba9e..3cf9e3c 100644
--- a/openbsc/src/gsm_data.c
+++ b/openbsc/src/gsm_data.c
@@ -169,6 +169,12 @@
 	bts->ms_max_power = 15;	/* dBm */
 	bts->si_common.cell_sel_par.cell_resel_hyst = 2; /* 4 dB */
 	bts->si_common.cell_sel_par.rxlev_acc_min = 0;
+	bts->si_common.neigh_list.data = bts->si_common.data.neigh_list;
+	bts->si_common.neigh_list.data_len =
+				sizeof(bts->si_common.data.neigh_list);
+	bts->si_common.cell_alloc.data = bts->si_common.data.cell_alloc;
+	bts->si_common.cell_alloc.data_len =
+				sizeof(bts->si_common.data.cell_alloc);
 
 	for (i = 0; i < ARRAY_SIZE(bts->gprs.nsvc); i++) {
 		bts->gprs.nsvc[i].bts = bts;
diff --git a/openbsc/src/system_information.c b/openbsc/src/system_information.c
index 60a8219..2d4ba20 100644
--- a/openbsc/src/system_information.c
+++ b/openbsc/src/system_information.c
@@ -23,6 +23,7 @@
 
 #include <errno.h>
 #include <string.h>
+#include <stdio.h>
 #include <sys/types.h>
 #include <netinet/in.h>
 
@@ -30,6 +31,7 @@
 #include <openbsc/gsm_data.h>
 #include <openbsc/abis_rsl.h>
 #include <openbsc/rest_octets.h>
+#include <openbsc/bitvec.h>
 
 #define GSM48_CELL_CHAN_DESC_SIZE	16
 #define GSM_MACBLOCK_LEN 		23
@@ -38,7 +40,7 @@
 /* Frequency Lists as per TS 04.08 10.5.2.13 */
 
 /* 10.5.2.13.2: Bit map 0 format */
-static int cchan_list_bm0_set_arfcn(u_int8_t *chan_list, unsigned int arfcn)
+static int freq_list_bm0_set_arfcn(u_int8_t *chan_list, unsigned int arfcn)
 {
 	unsigned int byte, bit;
 
@@ -57,7 +59,7 @@
 }
 
 /* 10.5.2.13.7: Variable bit map format */
-static int cchan_list_bmrel_set_arfcn(u_int8_t *chan_list, unsigned int arfcn)
+static int freq_list_bmrel_set_arfcn(u_int8_t *chan_list, unsigned int arfcn)
 {
 	unsigned int byte, bit;
 	unsigned int min_arfcn;
@@ -86,20 +88,23 @@
 }
 
 /* generate a cell channel list as per Section 10.5.2.1b of 04.08 */
-static int generate_cell_chan_list(u_int8_t *chan_list, const struct gsm_bts *bts)
+static int bitvec2freq_list(u_int8_t *chan_list, struct bitvec *bv,
+			    const struct gsm_bts *bts)
 {
-	struct gsm_bts_trx *trx;
-	int rc, min = 1024, max = 0;
+	int i, rc, min = 1024, max = 0;
 
 	memset(chan_list, 0, 16);
 
 	/* GSM900-only handsets only support 'bit map 0 format' */
 	if (bts->band == GSM_BAND_900) {
 		chan_list[0] = 0;
-		llist_for_each_entry(trx, &bts->trx_list, list) {
-			rc = cchan_list_bm0_set_arfcn(chan_list, trx->arfcn);
-			if (rc < 0)
-				return rc;
+
+		for (i = 0; i < bv->data_len*8; i++) {
+			if (bitvec_get_bit_pos(bv, i)) {
+				rc = freq_list_bm0_set_arfcn(chan_list, i);
+				if (rc < 0)
+					return rc;
+			}
 		}
 		return 0;
 	}
@@ -107,11 +112,13 @@
 	/* We currently only support the 'Variable bitmap format' */
 	chan_list[0] = 0x8e;
 
-	llist_for_each_entry(trx, &bts->trx_list, list) {
-		if (trx->arfcn < min)
-			min = trx->arfcn;
-		if (trx->arfcn > max)
-			max = trx->arfcn;
+	for (i = 0; i < bv->data_len*8; i++) {
+		if (bitvec_get_bit_pos(bv, i)) {
+			if (i < min)
+				min = i;
+			if (i > max)
+				max = i;
+		}
 	}
 
 	if ((max - min) > 111)
@@ -121,8 +128,8 @@
 	chan_list[1] = (min >> 1);
 	chan_list[2] = (min & 1) << 7;
 
-	llist_for_each_entry(trx, &bts->trx_list, list) {
-		rc = cchan_list_bmrel_set_arfcn(chan_list, trx->arfcn);
+	for (i = 0; i < bv->data_len*8; i++) {
+		rc = freq_list_bmrel_set_arfcn(chan_list, i);
 		if (rc < 0)
 			return rc;
 	}
@@ -131,61 +138,37 @@
 }
 
 /* generate a cell channel list as per Section 10.5.2.1b of 04.08 */
-static int generate_bcch_chan_list(u_int8_t *chan_list, const struct gsm_bts *bts)
+static int generate_cell_chan_list(u_int8_t *chan_list, struct gsm_bts *bts)
 {
-	struct gsm_bts *cur_bts;
 	struct gsm_bts_trx *trx;
-	int rc, min = 1024, max = 0;
+	struct bitvec *bv = &bts->si_common.cell_alloc;
 
-	memset(chan_list, 0, 16);
+	/* first we generate a bitvec of all TRX ARFCN's in our BTS */
+	llist_for_each_entry(trx, &bts->trx_list, list)
+		bitvec_set_bit_pos(bv, trx->arfcn, 1);
 
-	/* GSM900-only handsets only support 'bit map 0 format' */
-	if (bts->band == GSM_BAND_900) {
-		chan_list[0] = 0;
-		llist_for_each_entry(cur_bts, &bts->list, list) {
-			if (&cur_bts->list == &bts->network->bts_list)
-				continue;
-			trx = cur_bts->c0;
-			rc = cchan_list_bm0_set_arfcn(chan_list, trx->arfcn);
-			if (rc < 0)
-				return rc;
-		}
-		return 0;
-	}
-
-	/* We currently only support the 'Variable bitmap format' */
-	chan_list[0] = 0x8e;
-
-	llist_for_each_entry(cur_bts, &bts->list, list) {
-		if (&cur_bts->list == &bts->network->bts_list)
-			continue;
-		trx = cur_bts->c0;
-		if (trx->arfcn < min)
-			min = trx->arfcn;
-		if (trx->arfcn > max)
-			max = trx->arfcn;
-	}
-
-	if ((max - min) > 111)
-		return -EINVAL;
-
-	chan_list[0] |= (min >> 9) & 1;
-	chan_list[1] = (min >> 1);
-	chan_list[2] = (min & 1) << 7;
-
-	llist_for_each_entry(cur_bts, &bts->list, list) {
-		if (&cur_bts->list == &bts->network->bts_list)
-			continue;
-		trx = cur_bts->c0;
-		rc = cchan_list_bmrel_set_arfcn(chan_list, trx->arfcn);
-		if (rc < 0)
-			return rc;
-	}
-
-	return 0;
+	/* then we generate a GSM 04.08 frequency list from the bitvec */
+	return bitvec2freq_list(chan_list, bv, bts);
 }
 
-static int generate_si1(u_int8_t *output, const struct gsm_bts *bts)
+/* generate a cell channel list as per Section 10.5.2.1b of 04.08 */
+static int generate_bcch_chan_list(u_int8_t *chan_list, struct gsm_bts *bts)
+{
+	struct gsm_bts *cur_bts;
+	struct bitvec *bv = &bts->si_common.neigh_list;
+
+	/* first we generate a bitvec of the BCCH ARFCN's in our BSC */
+	llist_for_each_entry(cur_bts, &bts->network->bts_list, list) {
+		if (cur_bts == bts)
+			continue;
+		bitvec_set_bit_pos(bv, cur_bts->c0->arfcn, 1);
+	}
+
+	/* then we generate a GSM 04.08 frequency list from the bitvec */
+	return bitvec2freq_list(chan_list, bv, bts);
+}
+
+static int generate_si1(u_int8_t *output, struct gsm_bts *bts)
 {
 	int rc;
 	struct gsm48_system_information_type_1 *si1 =
@@ -210,7 +193,7 @@
 	return GSM_MACBLOCK_LEN;
 }
 
-static int generate_si2(u_int8_t *output, const struct gsm_bts *bts)
+static int generate_si2(u_int8_t *output, struct gsm_bts *bts)
 {
 	int rc;
 	struct gsm48_system_information_type_2 *si2 =
@@ -257,7 +240,7 @@
 	.break_ind = 0,
 };
 
-static int generate_si3(u_int8_t *output, const struct gsm_bts *bts)
+static int generate_si3(u_int8_t *output, struct gsm_bts *bts)
 {
 	struct gsm48_system_information_type_3 *si3 =
 		(struct gsm48_system_information_type_3 *) output;
@@ -287,7 +270,7 @@
 	return GSM_MACBLOCK_LEN;
 }
 
-static int generate_si4(u_int8_t *output, const struct gsm_bts *bts)
+static int generate_si4(u_int8_t *output, struct gsm_bts *bts)
 {
 	struct gsm48_system_information_type_4 *si4 =
 		(struct gsm48_system_information_type_4 *) output;
@@ -319,7 +302,7 @@
 	return GSM_MACBLOCK_LEN;
 }
 
-static int generate_si5(u_int8_t *output, const struct gsm_bts *bts)
+static int generate_si5(u_int8_t *output, struct gsm_bts *bts)
 {
 	struct gsm48_system_information_type_5 *si5 =
 		(struct gsm48_system_information_type_5 *) output;
@@ -339,7 +322,7 @@
 	return 18;
 }
 
-static int generate_si6(u_int8_t *output, const struct gsm_bts *bts)
+static int generate_si6(u_int8_t *output, struct gsm_bts *bts)
 {
 	struct gsm48_system_information_type_6 *si6 =
 		(struct gsm48_system_information_type_6 *) output;
@@ -390,7 +373,7 @@
 	},
 };
 
-static int generate_si13(u_int8_t *output, const struct gsm_bts *bts)
+static int generate_si13(u_int8_t *output, struct gsm_bts *bts)
 {
 	struct gsm48_system_information_type_13 *si13 =
 		(struct gsm48_system_information_type_13 *) output;