diff --git a/libisoburn/trunk/xorriso/text_io.c b/libisoburn/trunk/xorriso/text_io.c
index 4b747f45..079d3c58 100644
--- a/libisoburn/trunk/xorriso/text_io.c
+++ b/libisoburn/trunk/xorriso/text_io.c
@@ -1954,8 +1954,7 @@ int Xorriso_sieve_get_result(struct XorrisO *xorriso, char *name,
    }
    if(f->next_to_deliver == NULL) {
      /* Should not happen */
-     *available= 0;
- break;
+     goto unexpected_null;
    }
    if(f->num_words <= 0)
      return(1);
@@ -1974,9 +1973,15 @@ int Xorriso_sieve_get_result(struct XorrisO *xorriso, char *name,
        if((*argv)[i] == NULL)
          goto no_mem;
      } else {
-
-       /* >>> ??? should not happen */;
-
+       /* should not happen */
+unexpected_null:;
+       Xorriso_msgs_submit(xorriso, 0,
+                    "Program error: Unexpected NULL pointer in message sieve.",
+                    0, "WARNING", 0);
+       if(*argv != NULL)
+         Xorriso__dispose_words(argc, argv);
+       *available= 0;
+       return(-2);
      }
      lst= Xorriso_lst_get_next(lst, 0);
    }
diff --git a/libisoburn/trunk/xorriso/xorriso_timestamp.h b/libisoburn/trunk/xorriso/xorriso_timestamp.h
index 5d729eaa..c1372512 100644
--- a/libisoburn/trunk/xorriso/xorriso_timestamp.h
+++ b/libisoburn/trunk/xorriso/xorriso_timestamp.h
@@ -1 +1 @@
-#define Xorriso_timestamP "2015.11.09.133135"
+#define Xorriso_timestamP "2015.11.10.084903"