anchor.diff:      sha256 = "19ffec70f9678f5c159feadc036ca47720681b782910fbaa95aa3867e7e86d8e";
     };
     arpack_src = fetchurl {
  -    url = "http://forge.scilab.org/index.php/p/arpack-ng/downloads/417/get/";
  +    url = "http://forge.scilab.org/index.php/p/arpack-ng/downloads/497/get/";
       name = "arpack-ng_${arpack_ver}.tar.gz";
  -    sha256 = "be250947a7d6eac7dff8c058102fce9922c524aa06be2a090b6e0bb2d1e228cd";
  +    sha256 = "1wk06bdjgap4hshx0lswzi7vxy2lrdx353y1k7yvm97mpsjvsf4k";
     };
     lapack_src = fetchurl {
       url = "http://www.netlib.org/lapack/lapack-${lapack_ver}.tgz";
  
positive.code: in
  stdenv.mkDerivation rec {
    pname = "julia";
    date = "20120801";
    name = "${pname}-git-${date}";
  
    grisu_ver = "1.1.1";
    dsfmt_ver = "2.1";
    openblas_ver = "v0.2.2";
    lapack_ver = "3.4.1";
    arpack_ver = "3.1.1";
    clp_ver = "1.14.5";
    lighttpd_ver = "1.4.29";
  
  
negative.code: 
    src = fetchgit {
      url = "git://github.com/JuliaLang/julia.git";
      rev = "4f692899688f500c77d768f67748f4b7335c90eb";
      sha256 = "a60e684a5283e80619f28ec8ff16fdc76c549e8463059507b0819db09dae6688";
    };
  
    buildInputs = [ gfortran perl m4 gmp pcre llvm readline 
  