diff --git a/src/dnsmasq.h b/src/dnsmasq.h
index e0d33f6..3068f5f 100644
--- a/src/dnsmasq.h
+++ b/src/dnsmasq.h
@@ -566,7 +566,8 @@ struct pxe_service {
 
 /* vendorclass, userclass, remote-id or cicuit-id */
 struct dhcp_vendor {
-  int len, match_type, option;
+  int len, match_type;
+  unsigned int enterprise;
   char *data;
   struct dhcp_netid netid;
   struct dhcp_vendor *next;
diff --git a/src/helper.c b/src/helper.c
index db5f097..4e92d25 100644
--- a/src/helper.c
+++ b/src/helper.c
@@ -467,11 +467,17 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
 	buf = grab_extradata(buf, end, "DNSMASQ_VENDOR_CLASS", &err);
 #ifdef HAVE_DHCP6
       else
-	for (i = 0; i < data.hwaddr_len; i++)
-	  {
-	    sprintf(daemon->dhcp_buff2, "DNSMASQ_VENDOR_CLASS%i", i);
-	    buf = grab_extradata(buf, end, daemon->dhcp_buff2, &err);
-	  }
+	{
+	  if (data.hwaddr_len != 0)
+	    {
+	      buf = grab_extradata(buf, end, "DNSMASQ_VENDOR_CLASS_ID", &err);
+	      for (i = 0; i < data.hwaddr_len - 1; i++)
+		{
+		  sprintf(daemon->dhcp_buff2, "DNSMASQ_VENDOR_CLASS%i", i);
+		  buf = grab_extradata(buf, end, daemon->dhcp_buff2, &err);
+		}
+	    }
+	}
 #endif
 
       buf = grab_extradata(buf, end, "DNSMASQ_SUPPLIED_HOSTNAME", &err);
diff --git a/src/option.c b/src/option.c
index a9abbc7..2840670 100644
--- a/src/option.c
+++ b/src/option.c
@@ -2870,6 +2870,18 @@ static char *one_opt(int option, char *arg, char *gen_prob, int command_line)
 	    new->netid.net = opt_string_alloc(set_prefix(arg));
 	    /* check for hex string - must digits may include : must not have nothing else, 
 	       only allowed for agent-options. */
+
+	    arg = comma;
+	    if ((comma = split(arg)))
+	      {
+		if (option  != 'U' || strstr(arg, "enterprise:") != arg)
+		  option = '?';
+		else
+		  new->enterprise = atoi(arg+11);
+	      }
+	    else
+	      comma = arg;
+
 	    for (p = (unsigned char *)comma; *p; p++)
 	      if (isxdigit(*p))
 		dig = 1;
diff --git a/src/rfc3315.c b/src/rfc3315.c
index 8e0f1cc..7f5c35f 100644
--- a/src/rfc3315.c
+++ b/src/rfc3315.c
@@ -269,7 +269,20 @@ static int dhcp6_no_relay(int msg_type, struct dhcp_netid *tags, struct dhcp_con
       if ((opt = opt6_find(packet_options, end, mopt, 2)))
 	{
 	  void *enc_opt, *enc_end = opt6_ptr(opt, opt6_len(opt));
-	  for (enc_opt = opt6_ptr(opt, 0); enc_opt; enc_opt = opt6_next(enc_opt, enc_end))
+	  int offset = 0;
+	  
+	  if (mopt == OPTION6_VENDOR_CLASS)
+	    {
+	      if (opt6_len(opt) < 4)
+		continue;
+	      
+	      if (vendor->enterprise != opt6_uint(opt, 0, 4))
+		continue;
+	    
+	      offset = 4;
+	    }
+ 
+	  for (enc_opt = opt6_ptr(opt, offset); enc_opt; enc_opt = opt6_next(enc_opt, enc_end))
 	    for (i = 0; i <= (opt6_len(enc_opt) - vendor->len); i++)
 	      if (memcmp(vendor->data, opt6_ptr(enc_opt, i), vendor->len) == 0)
 		{
@@ -620,14 +633,20 @@ static int dhcp6_no_relay(int msg_type, struct dhcp_netid *tags, struct dhcp_con
 				lease->extradata_size = lease->extradata_len = 0;
 				lease->hwaddr_len = 0; /* surrogate for no of vendor classes */
 
-				if ((class_opt = opt6_find(packet_options, end, OPTION6_VENDOR_CLASS, 2)))
+				if ((class_opt = opt6_find(packet_options, end, OPTION6_VENDOR_CLASS, 4)))
 				  {
 				    void *enc_opt, *enc_end = opt6_ptr(class_opt, opt6_len(class_opt));
-				    for (enc_opt = opt6_ptr(class_opt, 0); enc_opt; enc_opt = opt6_next(enc_opt, enc_end))
-				      {
-					lease->hwaddr_len++;
-					lease_add_extradata(lease, opt6_ptr(enc_opt, 0), opt6_len(enc_opt), 0);
-				      }
+				    lease->hwaddr_len++;
+				    /* 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);
+				    
+				    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_add_extradata(lease, opt6_ptr(enc_opt, 0), opt6_len(enc_opt), 0);
+					}
 				  }
 				
 				lease_add_extradata(lease, (unsigned char *)client_hostname,