diff --git a/ospf6d/ospf6_proto.c b/ospf6d/ospf6_proto.c
new file mode 100644
index 0000000..71e575f
--- /dev/null
+++ b/ospf6d/ospf6_proto.c
@@ -0,0 +1,40 @@
+/*
+ * Copyright (C) 1999 Yasuhiro Ohara
+ *
+ * This file is part of GNU Zebra.
+ *
+ * GNU Zebra is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2, or (at your option) any
+ * later version.
+ *
+ * GNU Zebra is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Zebra; see the file COPYING.  If not, write to the 
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 
+ * Boston, MA 02111-1307, USA.  
+ */
+
+#include <zebra.h>
+
+#include "ospf6_proto.h"
+
+char *
+ospf6_options_string (u_char opt_capability[3], char *buffer, int size)
+{
+  char *dc, *r, *n, *mc, *e, *v6;
+
+  dc = (OSPF6_OPT_ISSET (opt_capability, OSPF6_OPT_DC) ? "DC" : "--");
+  r  = (OSPF6_OPT_ISSET (opt_capability, OSPF6_OPT_R) ? "R" : "-");
+  n  = (OSPF6_OPT_ISSET (opt_capability, OSPF6_OPT_N) ? "N" : "-");
+  mc = (OSPF6_OPT_ISSET (opt_capability, OSPF6_OPT_MC) ? "MC" : "--");
+  e  = (OSPF6_OPT_ISSET (opt_capability, OSPF6_OPT_E) ? "E" : "-");
+  v6 = (OSPF6_OPT_ISSET (opt_capability, OSPF6_OPT_V6) ? "V6" : "--");
+  snprintf (buffer, size, "%s|%s|%s|%s|%s|%s", dc, r, n, mc, e, v6);
+  return buffer;
+}
+