diff --git a/.gitignore b/.gitignore
index 81f96c69..9bbe8d6f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -25,3 +25,5 @@ bochs/libtool
 bochs/ltdlconf.h
 
 !bochs/plex86/kernel/freebsd/Makefile
+
+simulators/gem5/*
diff --git a/doc/how-to-build.txt b/doc/how-to-build.txt
index ac81eaf0..eb2c3a1b 100644
--- a/doc/how-to-build.txt
+++ b/doc/how-to-build.txt
@@ -19,6 +19,14 @@ Required for the Bochs simulator backend:
  - libpthread
  - Probably more, depending on, e.g., the GUI you configure (X11 ->
    libxrandr-dev)
+   
+Required for the gem5 simulator backend:
+**********************************************************************
+ - SCons
+ - SWIG
+ - zlib
+ - m4
+ - python-dev
 
 For distribution/parallelization:
 **********************************************************************
@@ -193,3 +201,23 @@ For the first time:
     /fs/proj/compiler/codesourcery-arm-eabi (DO, ios/kos)
 TODO: Source setup.sh, setupImperas ...
 TODO: Fix Hard-coded paths
+
+Building gem5:
+**********************************************************************
+
+For the first time:
+------------------------------------------------------------
+ 1. Change to the gem5 simulator directory (expects to be in ${FAIL_DIR}):
+      $ cd simulators/gem5
+ 2. Get the gem5 sourcecode from the stable repository (Mercurial needed)
+      $ hg clone http://repo.gem5.org/gem5-stable ./
+
+Optimized build:
+------------------------------------------------------------
+      $ cd ../simulator/gem5
+      $ scons EXTRAS=../../src/core/sal/gem5 build/ARM/gem5.fast
+
+Debug build:
+------------------------------------------------------------
+      $ cd ../simulator/gem5
+      $ scons EXTRAS=../../src/core/sal/gem5 build/ARM/gem5.debug
diff --git a/simulators/gem5/build_debug.sh b/simulators/gem5/build_debug.sh
deleted file mode 100644
index 18c1f028..00000000
--- a/simulators/gem5/build_debug.sh
+++ /dev/null
@@ -1 +0,0 @@
-scons EXTRAS=../../src/core/sal/gem5  --colors build/ARM/gem5.debug -j4