diff --git a/lib/fko_encode.c b/lib/fko_encode.c
index c92d421..7dbb953 100644
--- a/lib/fko_encode.c
+++ b/lib/fko_encode.c
@@ -144,6 +144,7 @@ fko_encode_spa_data(fko_ctx_t ctx)
         free(tbuf);
         return(res);
     }
+    tbuf[strlen(tbuf)-2] = 0x2a;
 
     /* If a nat_access message was given, add it to the SPA
      * message.
