diff --git a/xorriso/write_run.c b/xorriso/write_run.c
index 54eb672c..24e80e4d 100644
--- a/xorriso/write_run.c
+++ b/xorriso/write_run.c
@@ -455,8 +455,10 @@ int Xorriso_set_system_area(struct XorrisO *xorriso, struct burn_drive *drive,
      system_area_options= xorriso->patch_system_area;
      /* Check whether partition 1 ends at image end */;
      ub= (unsigned char *) buf;
-     hd_lba= (ub[454] | (ub[455] << 8) | (ub[456] << 16) | (ub[457] << 24)) +
-             (ub[458] | (ub[459] << 8) | (ub[460] << 16) | (ub[461] << 24));
+     hd_lba= (ub[454] | (ub[455] << 8) | (ub[456] << 16) |
+              (((unsigned int) ub[457]) << 24)) +
+             (ub[458] | (ub[459] << 8) | (ub[460] << 16) |
+              (((unsigned int) ub[461]) << 24));
 
      iso_lba= -1;
      ret= isoburn_disc_get_msc1(drive, &start_lba);
diff --git a/xorriso/xorriso_timestamp.h b/xorriso/xorriso_timestamp.h
index d73d1dc5..eb8031e7 100644
--- a/xorriso/xorriso_timestamp.h
+++ b/xorriso/xorriso_timestamp.h
@@ -1 +1 @@
-#define Xorriso_timestamP "2015.11.04.094803"
+#define Xorriso_timestamP "2015.11.04.100839"