diff --git a/pkgs/development/libraries/mpich2/default.nix b/pkgs/development/libraries/mpich2/default.nix
index 7fb0e009f4ae..9e0920eb1c42 100644
--- a/pkgs/development/libraries/mpich2/default.nix
+++ b/pkgs/development/libraries/mpich2/default.nix
@@ -1,16 +1,34 @@
-{stdenv, fetchurl, python}:
+{ stdenv, fetchurl, python, perl }:
+
+let version = "1.2.1"; in
+stdenv.mkDerivation {
+  name = "mpich2-${version}";
 
-stdenv.mkDerivation rec {
-  name = "mpich2-1.0.6p1";
-  
   src = fetchurl {
-    url = "http://www.mcs.anl.gov/research/projects/mpich2/downloads/tarballs/${name}.tar.gz";
-    sha256 = "1k0za8951j5fn89ww6bsy9b4yi989zz7bnd8a6acfr8r0yb8z01q";
+    url = "http://www.mcs.anl.gov/research/projects/mpich2/downloads/tarballs/${version}/mpich2-${version}.tar.gz";
+    sha256 = "1h91hygal4h33yci7sw76hibf803r9c0mx7kfgmc06h27xa3cirr";
   };
 
-  buildInputs = [ python ];
+  buildInputs = [ python perl ];
+
+  patchPhase =
+    '' for i in $(find -type f -not -name Makefile.\*)
+       do
+         if grep -q /usr/bin/env "$i"
+         then
+             interpreter="$(cat $i | grep /usr/bin/env | sed -'es|^.*/usr/bin/env \([^ ]\+\).*$|\1|g')"
+             echo "file \`$i' -> interpreter \`$interpreter'"
+             path="$(type -P $interpreter)"
+             echo "\`/usr/bin/env $interpreter' -> \`$path' in \`$i'..."
+             sed -i "$i" -e "s|/usr/bin/env $interpreter|$path|g"
+         fi
+       done
+       true
+    '';
 
   meta = {
+    description = "MPICH2, an implementation of the Message Passing Interface (MPI) standard";
+
     longDescription = ''
       MPICH2 is a free high-performance and portable implementation of
       the Message Passing Interface (MPI) standard, both version 1 and
@@ -18,5 +36,8 @@ stdenv.mkDerivation rec {
     '';
     homepage = http://www.mcs.anl.gov/mpi/mpich2/;
     license = "free, see http://www.mcs.anl.gov/research/projects/mpich2/downloads/index.php?s=license";
+
+    maintainers = [ stdenv.lib.maintainers.ludo ];
+    platforms = stdenv.lib.platforms.unix;
   };
 }
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 5895f0e395cd..6f77d1d27eda 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -4355,7 +4355,7 @@ let
   };
 
   mpich2 = import ../development/libraries/mpich2 {
-    inherit fetchurl stdenv python;
+    inherit fetchurl stdenv python perl;
   };
 
   muparser = import ../development/libraries/muparser {