diff --git a/CHANGELOG b/CHANGELOG
index 3919d1d..8b57a36 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -144,6 +144,11 @@ version 2.67
 	    target of --cname. Thanks to Hadmut Danisch for the
 	    suggestion. 
 
+	    Avoid treating a --dhcp-host which has an IPv6 address
+	    as eligable for use with DHCPv4 on the grounds that it has
+	    no address, and vice-versa. Thanks to Yury Konovalov for
+	    spotting the problem.
+
  
 version 2.66
             Add the ability to act as an authoritative DNS
diff --git a/src/dhcp-common.c b/src/dhcp-common.c
index 304c47e..5b0756d 100644
--- a/src/dhcp-common.c
+++ b/src/dhcp-common.c
@@ -272,27 +272,26 @@ static int is_config_in_context(struct dhcp_context *context, struct dhcp_config
   if (!context) /* called via find_config() from lease_update_from_configs() */
     return 1; 
 
-  if (!(context->flags & CONTEXT_V6))
-    {
-      if (!(config->flags & CONFIG_ADDR))
+  if (!(config->flags & (CONFIG_ADDR | CONFIG_ADDR6)))
+    return 1;
+  
+#ifdef HAVE_DHCP6
+  if ((context->flags & CONTEXT_V6) && (config->flags & CONFIG_WILDCARD))
+    return 1;
+#endif
+
+  for (; context; context = context->current)
+#ifdef HAVE_DHCP6
+    if (context->flags & CONTEXT_V6) 
+      {
+	if ((config->flags & CONFIG_ADDR6) && is_same_net6(&config->addr6, &context->start6, context->prefix))
+	  return 1;
+      }
+    else 
+#endif
+      if ((config->flags & CONFIG_ADDR) && is_same_net(config->addr, context->start, context->netmask))
 	return 1;
 
-      for (; context; context = context->current)
-	if (is_same_net(config->addr, context->start, context->netmask))
-	  return 1;
-    }
-#ifdef HAVE_DHCP6
-  else 
-    {
-      if (!(config->flags & CONFIG_ADDR6) || (config->flags & CONFIG_WILDCARD))
-	return 1;
-      
-      for (; context; context = context->current)
-	if (is_same_net6(&config->addr6, &context->start6, context->prefix))
-      return 1;
-    }
-#endif
-  
   return 0;
 }
 
diff --git a/src/rfc1035.c b/src/rfc1035.c
index 7c1c30d..c1dc716 100644
--- a/src/rfc1035.c
+++ b/src/rfc1035.c
@@ -644,20 +644,20 @@ size_t calc_subnet_opt(struct subnet_opt *opt, union mysockaddr *source)
   int len;
   void *addrp;
 
-  if (source->sa.sa_family == AF_INET)
-    {
-      opt->family = htons(1);
-      opt->source_netmask = daemon->addr4_netmask;
-      addrp = &source->in.sin_addr;
-    }
 #ifdef HAVE_IPV6
-  else
+  if (source->sa.sa_family == AF_INET6)
     {
       opt->family = htons(2);
       opt->source_netmask = daemon->addr6_netmask;
       addrp = &source->in6.sin6_addr;
     }
+  else
 #endif
+    {
+      opt->family = htons(1);
+      opt->source_netmask = daemon->addr4_netmask;
+      addrp = &source->in.sin_addr;
+    }
   
   opt->scope_netmask = 0;
   len = 0;