diff --git a/releng/README.releng b/releng/README.releng
index 90cfe743..81a6c46e 100644
--- a/releng/README.releng
+++ b/releng/README.releng
@@ -1,10 +1,10 @@
 Release Engineering Che[at|ck] List
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 * SOFTWARE TO TEST
-Use latest libraries code base from svn and bzr
-(see README for aditional and autodetected library dependencies)
-Alternatively, use latest all-in-one development tarball from:
-http://www.gnu.org/software/xorriso/
+ Use latest libraries code base from svn and bzr
+ (see README for aditional and autodetected library dependencies)
+ Alternatively, use latest all-in-one development tarball from:
+ http://www.gnu.org/software/xorriso/
 
 * SETUP THE TEST ENVIRONMENT
  + Not all TESTs are scripts (e.g. cppcheck, valgrind)
@@ -17,43 +17,44 @@ http://www.gnu.org/software/xorriso/
  + well documented configuration file test.conf{.template}
  + throw FAIL string to stdout if any failure is detected
  + exit code 0 on success, non-zero on failure
+ + use different exit codes for any failure (10, 20, ... 100)
 
 * TESTS LIST
 
-TEST: releng_build_os
-FILE: libburn/releng/releng_build_os
-WHO:  george, thomas
+ TEST: releng_build_os
+ FILE: libburn/releng/releng_build_os
+ WHO:  george, thomas
 
-TEST: releng_build_isojigdo
-FILE: libisoburn/releng/releng_build_isojigdo
-WHO:  george, thomas
+ TEST: releng_build_isojigdo
+ FILE: libisoburn/releng/releng_build_isojigdo
+ WHO:  george, thomas
 
-TEST: releng_check_isocontent
-FILE: libisoburn/releng/releng_check_isocontent
-WHO:  george, thomas
+ TEST: releng_check_isocontent
+ FILE: libisoburn/releng/releng_check_isocontent
+ WHO:  george, thomas
 
-TEST: valgrind
-FILE:
-WHO:  george, thomas
+ TEST: valgrind
+ FILE:
+ WHO:  george, thomas
 
-TEST: cppcheck
-FILE: http://people.debian.org/~danchev/xorriso/sclogs/
-WHO:  george, thomas
+ TEST: cppcheck
+ FILE: http://people.debian.org/~danchev/xorriso/sclogs/
+ WHO:  george, thomas
 
-TEST: buildd_logs
-FILE: http://buildd.debian.org (others are also welcome)
-FILE: (err/warn from prev. builds for several h/w architectures and kernels: linux, kfreebsd, hurd)
-WHO:  george, thomas
+ TEST: buildd_logs
+ FILE: http://buildd.debian.org (others are also welcome)
+ FILE: (err/warn from prev. builds for several h/w architectures and kernels: linux, kfreebsd, hurd)
+ WHO:  george, thomas
 
-TEST: medistimator (dialog mode, size estimation, processing large trees)
-      requires some specific knowledge of how the tool works, to interpret
-      the results and compare them previous runs (see comments in the source).
-FILE: http://anonscm.debian.org/gitweb/?p=users/danchev/medistimator.git;a=summary
-FILE: http://people.debian.org/~danchev/medistimator/log/
-WHO:  george, thomas
+ TEST: medistimator (dialog mode, size estimation, processing large trees)
+       requires some specific knowledge of how the tool works, to interpret
+       the results and compare them previous runs (see comments in the source).
+ FILE: http://anonscm.debian.org/gitweb/?p=users/danchev/medistimator.git;a=summary
+ FILE: http://people.debian.org/~danchev/medistimator/log/
+ WHO:  george, thomas
 
-TEST: gprof
-FILE: CFLAGS=-pg ./configure && make
-FILE: run resulting executable; gmon.out to be created in current cirectory
-FILE: gprof path/to/xorriso gmon.out  > gprof.out
-WHO:  george, thomas
+ TEST: gprof
+ FILE: CFLAGS=-pg ./configure && make
+ FILE: run resulting executable; gmon.out to be created in current cirectory
+ FILE: gprof path/to/xorriso gmon.out  > gprof.out
+ WHO:  george, thomas
diff --git a/releng/releng_build_isojigdo b/releng/releng_build_isojigdo
index 3584a60f..4021f88e 100755
--- a/releng/releng_build_isojigdo
+++ b/releng/releng_build_isojigdo
@@ -32,14 +32,14 @@ HLP
 }
 
 # help
-if [ ! "${1}" -o "${1}" == "-help" ]; then print_help && exit 0; fi
+if [ ! "${1}" -o "${1}" == "-help" ]; then print_help && exit 10; fi
 # config file
 if [ "${1}" == "-rc" ]; then
  if [ -e ${CONFFILE} ]; then
   . ${CONFFILE}
   printf "$0: Using config file %s\n" ${CONFFILE}
  else
-  echo -e "\n$0: Config file ${CONFFILE} not found.\n" && exit 1
+  echo -e "\n$0: Config file ${CONFFILE} not found.\n" && exit 20
  fi
  if [ "${2}" == "-clean" ]; then CLEAN=1; fi
 # command line args
@@ -54,17 +54,17 @@ elif [ "${3}" ]; then
  fi
 # the rest
 else
- print_help && exit 0
+ print_help && exit 30
 fi
 
 if [ "${XOR}" == "" -o "${DIR}" == "" -o "${IMG}" == "" ]; then
  echo -e "\n$0: xorriso_cmd IN_dir and OUT_image are required\n"
- exit 1
+ exit 40
 fi
 
 if [ ! -x "${XOR}" ]; then
  printf "$0: Not found or not an executable: $XOR\n"
- exit 1
+ exit 50
 fi
 
 # all must be set at this point
@@ -94,7 +94,7 @@ if which jigdo-gen-md5-list >/dev/null 2>&1; then
 else
  printf "\n$0: Not found: jigdo-gen-md5-list. Install jigit."
  printf "\n$0: See http://www.einval.com/~steve/software/JTE/\n"
- exit 1
+ exit 60
 fi
 
 # build the command - general section
@@ -149,7 +149,7 @@ if which jigit-mkimage >/dev/null 2>&1; then
 else
  printf "\n$0: Not found: jigit-mkimage. Install jigit."
  printf "\n$0: See http://www.einval.com/~steve/software/JTE/\n"
- exit 1
+ exit 70
 fi
 
 # trap the exit code of diff and let the Universe explode
@@ -168,7 +168,7 @@ esac
 if [ ${CLEAN} -eq 1 ]; then
  # safety net, just in case -> we want to be in the starting
  # directory before removing whatever self-generated stuff
- cd "${START_DIR_DONT_CHANGE}" || exit 1
+ cd "${START_DIR_DONT_CHANGE}" || exit 80
  rm -f ${RES}
  printf "$0: removed %s\n" ${RES}
 else