diff --git a/pidl/lib/Parse/Pidl/Wireshark/NDR.pm b/pidl/lib/Parse/Pidl/Wireshark/NDR.pm
index 8161646..6868e52 100644
--- a/pidl/lib/Parse/Pidl/Wireshark/NDR.pm
+++ b/pidl/lib/Parse/Pidl/Wireshark/NDR.pm
@@ -229,6 +229,7 @@ sub Bitmap($$$$)
 			$total_ev += hex($ev);
 			$self->pidl_code("&$hf_bitname,");
 		}
+		$self->pidl_code("NULL");
 		$self->deindent;
 		$self->pidl_code("};");
 	}