diff -ur olsrd.old/src/cfgparser/oparse.c olsrd.dev/src/cfgparser/oparse.c
--- olsrd.old/src/cfgparser/oparse.c	2006-01-01 17:15:57.000000000 +0100
+++ olsrd.dev/src/cfgparser/oparse.c	2006-10-09 01:06:27.000000000 +0200
@@ -1921,6 +1921,7 @@
       return -1;
     }
   h->netmask.v4 = in.s_addr;
+  h->net.v4 &= h->netmask.v4;
   /* Queue */
   h->next = cnf->hna4_entries;
   cnf->hna4_entries = h;