diff --git a/openbsc/src/gprs/gprs_subscriber.c b/openbsc/src/gprs/gprs_subscriber.c
index 5b0bf39..648f912 100644
--- a/openbsc/src/gprs/gprs_subscriber.c
+++ b/openbsc/src/gprs/gprs_subscriber.c
@@ -757,8 +757,9 @@
 	}
 
 	if (strcpy(subscr->equipment.imei, mmctx->imei) != 0) {
-		strncpy(subscr->equipment.imei, mmctx->imei, GSM_IMEI_LENGTH-1);
-		subscr->equipment.imei[GSM_IMEI_LENGTH-1] = 0;
+		strncpy(subscr->equipment.imei, mmctx->imei,
+			sizeof(subscr->equipment.imei)-1);
+		subscr->equipment.imei[sizeof(subscr->equipment.imei)-1] = 0;
 	}
 
 	if (subscr->lac != mmctx->ra.lac)