diff --git a/CHANGELOG b/CHANGELOG
index e1daeef..73b4c95 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,9 @@
+version 2.64
+            Handle DHCP FQDN options with all flag bits zero and
+            --dhcp-client-update set. Thanks to Bernd Krumbroeck for
+            spotting the problem.
+
+
 version 2.63
             Do duplicate dhcp-host address check in --test mode.
 
diff --git a/src/rfc2131.c b/src/rfc2131.c
index cf22c03..ff7e114 100644
--- a/src/rfc2131.c
+++ b/src/rfc2131.c
@@ -510,7 +510,8 @@
       char *pq = daemon->dhcp_buff;
       unsigned char *pp, *op = option_ptr(opt, 0);
       
-      fqdn_flags = *op;
+      /* Set an MBZ bit to indicate receipt of FQDN option - cleared later */
+      fqdn_flags = *op | 0x10;
       len -= 3;
       op += 3;
       pp = op;
@@ -2261,7 +2262,7 @@
 	  
 	  if ((p = free_space(mess, end, OPTION_CLIENT_FQDN, len)))
 	    {
-	      *(p++) = fqdn_flags;
+	      *(p++) = fqdn_flags & 0x0f; /* MBZ bits to zero */ 
 	      *(p++) = 255;
 	      *(p++) = 255;