diff --git a/src/dnsmasq.h b/src/dnsmasq.h
index 482af22..69ae7a7 100644
--- a/src/dnsmasq.h
+++ b/src/dnsmasq.h
@@ -543,6 +543,7 @@ struct dhcp_lease {
     int backoff; /* zero -> confirmed */
     struct slaac_address *next;
   } *slaac_address;
+  int vendorclass_count;
 #endif
   struct dhcp_lease *next;
 };
diff --git a/src/helper.c b/src/helper.c
index 94aabeb..ab691b7 100644
--- a/src/helper.c
+++ b/src/helper.c
@@ -655,8 +655,9 @@ void queue_script(int action, struct dhcp_lease *lease, char *hostname, time_t n
   unsigned char *p;
   unsigned int hostname_len = 0, clid_len = 0, ed_len = 0;
   int fd = daemon->dhcpfd;
+#ifdef HAVE_DHCP6 
+  int is6 = !!(lease->flags & (LEASE_TA | LEASE_NA));
 
-#ifdef HAVE_DHCP6
   if (!daemon->dhcp)
     fd = daemon->dhcp6fd;
 #endif
@@ -676,7 +677,12 @@ void queue_script(int action, struct dhcp_lease *lease, char *hostname, time_t n
 
   buf->action = action;
   buf->flags = lease->flags;
-  buf->hwaddr_len = lease->hwaddr_len;
+#ifdef HAVE_DHCP6 
+  if (is6)
+    buf->hwaddr_len = lease->vendorclass_count;
+  else
+#endif
+    buf->hwaddr_len = lease->hwaddr_len;
   buf->hwaddr_type = lease->hwaddr_type;
   buf->clid_len = clid_len;
   buf->ed_len = ed_len;
diff --git a/src/rfc3315.c b/src/rfc3315.c
index 9d11fe1..c8ba3d0 100644
--- a/src/rfc3315.c
+++ b/src/rfc3315.c
@@ -1609,12 +1609,12 @@ static void update_leases(struct state *state, struct dhcp_context *context, str
 	  free(lease->extradata);
 	  lease->extradata = NULL;
 	  lease->extradata_size = lease->extradata_len = 0;
-	  lease->hwaddr_len = 0; /* surrogate for no of vendor classes */
+	  lease->vendorclass_count = 0; 
 	  
 	  if ((class_opt = opt6_find(state->packet_options, state->end, OPTION6_VENDOR_CLASS, 4)))
 	    {
 	      void *enc_opt, *enc_end = opt6_ptr(class_opt, opt6_len(class_opt));
-	      lease->hwaddr_len++;
+	      lease->vendorclass_count++;
 	      /* send enterprise number first  */
 	      sprintf(daemon->dhcp_buff2, "%u", opt6_uint(class_opt, 0, 4));
 	      lease_add_extradata(lease, (unsigned char *)daemon->dhcp_buff2, strlen(daemon->dhcp_buff2), 0);
@@ -1622,7 +1622,7 @@ static void update_leases(struct state *state, struct dhcp_context *context, str
 	      if (opt6_len(class_opt) >= 6) 
 		for (enc_opt = opt6_ptr(class_opt, 4); enc_opt; enc_opt = opt6_next(enc_opt, enc_end))
 		  {
-		    lease->hwaddr_len++;
+		    lease->vendorclass_count++;
 		    lease_add_extradata(lease, opt6_ptr(enc_opt, 0), opt6_len(enc_opt), 0);
 		  }
 	    }