diff --git a/openbsc/include/openbsc/gprs_llc.h b/openbsc/include/openbsc/gprs_llc.h
index 21ebaa2..4828a8f 100644
--- a/openbsc/include/openbsc/gprs_llc.h
+++ b/openbsc/include/openbsc/gprs_llc.h
@@ -82,9 +82,12 @@
 	uint32_t tlli;
 	uint32_t sapi;
 
-	uint8_t v_sent;
-	uint8_t v_ack;
-	uint8_t v_recv;
+	uint16_t v_sent;
+	uint16_t v_ack;
+	uint16_t v_recv;
+
+	uint16_t vu_send;
+	uint16_t vu_recv;
 
 	unsigned int n200;
 	unsigned int retrans_ctr;
diff --git a/openbsc/src/gprs/gprs_llc.c b/openbsc/src/gprs/gprs_llc.c
index 293c657..68d7d76 100644
--- a/openbsc/src/gprs/gprs_llc.c
+++ b/openbsc/src/gprs/gprs_llc.c
@@ -230,6 +230,10 @@
 	lle->bvci = msgb_bvci(msg);
 	lle->nsei = msgb_nsei(msg);
 
+	/* Increment V(U) */
+	nu = lle->vu_send;
+	lle->vu_send = (lle->vu_send + 1) % 512;
+
 	/* Address Field */
 	addr = sapi & 0xf;
 	if (command)