anchor.diff:  in
   
   stdenv.mkDerivation {
  -  name = "nss-3.12.8";
  -  
  +  name = "nss-3.13.3";
  +
     src = fetchurl {
  -    url = http://ftp.mozilla.org/pub/mozilla.org/security/nss/releases/NSS_3_12_8_RTM/src/nss-3.12.8.tar.gz;
  -    sha256 = "050c175l5zyzqxcp5fxj4q4n641c3j7w6w6fjg5hk3cyfhlwwy4i";
  +    url = http://ftp.mozilla.org/pub/mozilla.org/security/nss/releases/NSS_3_13_3_RTM/src/nss-3.13.3.tar.gz;
  +    sha256 = "efa10f2c70da4bddabf1a6081964969bb23359b93d6eadbf4739274a77bc3587";
     };
   
     buildInputs = [nspr perl zlib];
  
positive.code: 
        # Borrowed from Gentoo.  Firefox expects an nss-config script,
        # but NSS doesn't provide it.
        
        NSS_VMAJOR=`cat lib/nss/nss.h | grep "#define.*NSS_VMAJOR" | awk '{print $3}'`
        NSS_VMINOR=`cat lib/nss/nss.h | grep "#define.*NSS_VMINOR" | awk '{print $3}'`
        NSS_VPATCH=`cat lib/nss/nss.h | grep "#define.*NSS_VPATCH" | awk '{print $3}'`
  
negative.code: 
    # Based on the build instructions at
    # http://www.mozilla.org/projects/security/pki/nss/nss-3.11.4/nss-3.11.4-build.html
  
    postPatch = ''
      sed -i -e "/^PREFIX =/s:= /usr:= $out:" mozilla/security/nss/config/Makefile
    '';
  
    preConfigure = "cd mozilla/security/nss";
  