diff --git a/pkgs/development/compilers/gcc-4.0/default.nix b/pkgs/development/compilers/gcc-4.0/default.nix
index 5d81ecbfd74d..e25145cb623d 100644
--- a/pkgs/development/compilers/gcc-4.0/default.nix
+++ b/pkgs/development/compilers/gcc-4.0/default.nix
@@ -1,7 +1,8 @@
 { stdenv, fetchurl, noSysDirs
 , langC ? true, langCC ? true, langF77 ? false
 , profiledCompiler ? false
-,gmp ? null , mpfr ? null
+, gmp ? null , mpfr ? null
+, texinfo ? null
 }:
 
 assert langC;
@@ -21,10 +22,7 @@ stdenv.mkDerivation {
     
   inherit noSysDirs langC langCC langF77 profiledCompiler;
 
-  buildInputs = [] 
-	++ (if gmp != null then [gmp] else [])
-	++ (if mpfr != null then [mpfr] else [])
-	;
+  buildInputs = [gmp mpfr texinfo];
 
   configureFlags = "
     --disable-multilib
diff --git a/pkgs/development/compilers/gcc-4.1/default.nix b/pkgs/development/compilers/gcc-4.1/default.nix
index 621f96e49f95..3034bd5da8f2 100644
--- a/pkgs/development/compilers/gcc-4.1/default.nix
+++ b/pkgs/development/compilers/gcc-4.1/default.nix
@@ -4,13 +4,14 @@
 , staticCompiler ? false
 , gmp ? null
 , mpfr ? null
+, texinfo ? null
 }:
 
 assert langC || langF77;
 
 with import ../../../lib;
 
-stdenv.mkDerivation ({
+stdenv.mkDerivation {
   name = "gcc-4.1.2";
   builder = if langF77 then ./fortran.sh else  ./builder.sh;
   
@@ -33,6 +34,8 @@ stdenv.mkDerivation ({
     
   inherit noSysDirs profiledCompiler staticCompiler;
 
+  buildInputs = [gmp mpfr texinfo];
+  
   configureFlags = "
     --disable-multilib
     --disable-libstdcxx-pch
@@ -62,9 +65,3 @@ stdenv.mkDerivation ({
     priority = "7";
   };
 }
-
-// (if gmp != null || mpfr != null then {
-  buildInputs = []
-    ++ (if gmp != null then [gmp] else [])
-    ++ (if mpfr != null then [mpfr] else []);
-} else {}))
diff --git a/pkgs/development/compilers/gcc-4.2/default.nix b/pkgs/development/compilers/gcc-4.2/default.nix
index 7fcf7717c5a2..8c442ddca0ce 100644
--- a/pkgs/development/compilers/gcc-4.2/default.nix
+++ b/pkgs/development/compilers/gcc-4.2/default.nix
@@ -2,6 +2,7 @@
 , langC ? true, langCC ? true, langF77 ? false
 , profiledCompiler ? false
 , staticCompiler ? false
+, texinfo ? null
 }:
 
 assert langC;
@@ -34,6 +35,8 @@ stdenv.mkDerivation {
     
   inherit noSysDirs profiledCompiler staticCompiler;
 
+  buildInputs = [texinfo];
+
   configureFlags = "
     --disable-multilib
     --disable-libstdcxx-pch
diff --git a/pkgs/development/libraries/mpich2/default.nix b/pkgs/development/libraries/mpich2/default.nix
new file mode 100644
index 000000000000..b92eed68bdea
--- /dev/null
+++ b/pkgs/development/libraries/mpich2/default.nix
@@ -0,0 +1,20 @@
+{stdenv, fetchurl, python}:
+
+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";
+  };
+
+  buildInputs = [ python ];
+
+  meta = {
+    description = ''MPICH2 is a free high-performance and portable
+                    implementation of the Message Passing Interface
+		    (MPI) standard, both version 1 and version 2.'';
+    homepage = http://www.mcs.anl.gov/mpi/mpich2/;
+    license = "free, see http://www.mcs.anl.gov/research/projects/mpich2/downloads/index.php?s=license";
+  };
+}
diff --git a/pkgs/development/tools/misc/texinfo/4.9.nix b/pkgs/development/tools/misc/texinfo/4.9.nix
new file mode 100644
index 000000000000..fd42093e561d
--- /dev/null
+++ b/pkgs/development/tools/misc/texinfo/4.9.nix
@@ -0,0 +1,10 @@
+{stdenv, fetchurl, ncurses}:
+
+stdenv.mkDerivation {
+  name = "texinfo-4.9";
+  src = fetchurl {
+    url = mirror://gnu/texinfo/texinfo-4.9.tar.bz2;
+    sha256 = "0h7q9h405m88fjj067brzniiv8306ryl087pgjpmbpd2jci9h6g7";
+  };
+  buildInputs = [ncurses];
+}
diff --git a/pkgs/tools/package-management/nix/unstable.nix b/pkgs/tools/package-management/nix/unstable.nix
index 1a507f20a043..bfcf3697d8a9 100644
--- a/pkgs/tools/package-management/nix/unstable.nix
+++ b/pkgs/tools/package-management/nix/unstable.nix
@@ -3,14 +3,14 @@
 , stateDir ? "/nix/var"
 }:
 
-let version = "0.12pre10505"; in
+let version = "0.12pre10798"; in
 
 stdenv.mkDerivation {
   name = "nix-${version}";
   
   src = fetchurl {
     url = "http://nix.cs.uu.nl/dist/nix/nix-${version}/nix-${version}.tar.bz2";
-    md5 = "44dd2927ce97f12b3f110a7ad991828e";
+    md5 = "1f3d0a72c9bf1297c2daa32e601bde82";
   };
 
   buildInputs = [perl curl openssl];
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index cf62aa084b17..d105b65d4e0f 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -1093,18 +1093,26 @@ rec {
     inherit fetchurl stdenv noSysDirs;
   });
 
+  # XXX: GCC 4.2 (and possibly others) misdetects `makeinfo' when
+  # using Texinfo >= 4.10, just because it uses a stupid regexp that
+  # expects a single digit after the dot.  As a workaround, we feed
+  # GCC with Texinfo 4.9.  Stupid bug, hackish workaround.
+
   gcc40 = wrapGCC (import ../development/compilers/gcc-4.0 {
     inherit fetchurl stdenv noSysDirs;
+    texinfo = texinfo49;
     profiledCompiler = true;
   });
 
   gcc41 = wrapGCC (import ../development/compilers/gcc-4.1 {
     inherit fetchurl stdenv noSysDirs;
+    texinfo = texinfo49;
     profiledCompiler = false;
   });
 
   gcc42 = useFromStdenv "gcc" (wrapGCC (import ../development/compilers/gcc-4.2 {
     inherit fetchurl stdenv noSysDirs;
+    texinfo = texinfo49;
     profiledCompiler = true;
   }));
 
@@ -1975,6 +1983,10 @@ rec {
     javaSupport = true;
   }));
 
+  texinfo49 = import ../development/tools/misc/texinfo/4.9.nix {
+    inherit fetchurl stdenv ncurses;
+  };
+
   texinfo = import ../development/tools/misc/texinfo {
     inherit fetchurl stdenv ncurses;
   };
@@ -2738,6 +2750,10 @@ rec {
     inherit fetchurl stdenv ilbc mediastreamer pkgconfig;
   };
 
+  mpich2 = import ../development/libraries/mpich2 {
+    inherit fetchurl stdenv python;
+  };
+
   mysqlConnectorODBC = import ../development/libraries/mysql-connector-odbc {
     inherit fetchurl stdenv mysql libtool zlib unixODBC;
   };
@@ -5700,17 +5716,16 @@ rec {
     db4 = db45;
   };
 
-  nixCustomFun = src: preConfigure: configureFlags :
-  (import ../tools/package-management/nix/custom.nix {
-    inherit fetchurl stdenv perl curl bzip2 openssl src preConfigure automake 
+  nixCustomFun = src: preConfigure: configureFlags:
+    import ../tools/package-management/nix/custom.nix {
+      inherit fetchurl stdenv perl curl bzip2 openssl src preConfigure automake 
         autoconf libtool configureFlags;
-    bison = bison23;
-    flex = flex2533;
-    aterm = aterm242fixes;
-    db4 = db45;
-    inherit docbook5_xsl libxslt docbook5 docbook_xml_dtd_43 w3m;
-
-  });
+      bison = bison23;
+      flex = flex2533;
+      aterm = aterm242fixes;
+      db4 = db45;
+      inherit docbook5_xsl libxslt docbook5 docbook_xml_dtd_43 w3m;
+    };
 
   ntfs3g = import ../misc/ntfs-3g {
     inherit fetchurl stdenv fuse pkgconfig;