diff --git a/pkgs/development/python-modules/virtualenv-change-prefix.patch b/pkgs/development/python-modules/virtualenv-change-prefix.patch
index 5093fdbead94..d3e588bd1cd2 100644
--- a/pkgs/development/python-modules/virtualenv-change-prefix.patch
+++ b/pkgs/development/python-modules/virtualenv-change-prefix.patch
@@ -1,29 +1,32 @@
 Without this patch `virtualenv --python=python2.7 .` fails with an error because it notices that the python readline.so is not in the same path as python2.7. I assume this is to avoid copying the wrong file on systems where it is possible to find incompatible libraries by accident. Adding "/nix/store" to the prefix fixes this problem. Unfortunately readline is still not available if you just run `virtualenv .`.
 
-
---- virtualenv-1.6.4/virtualenv.py	2012-05-20 00:40:38.070649647 +0200
-+++ virtualenv-1.6.4/virtualenv.py	2012-05-20 00:45:10.596242604 +0200
-@@ -951,13 +951,7 @@
+--- virtualenv-1.8.4/virtualenv.py        2013-01-16 23:43:37.583615220 +0100
++++ virtualenv-1.8.4/virtualenv.py        2013-01-16 23:44:47.885973431 +0100
+@@ -1135,17 +1135,7 @@
  
  
  def change_prefix(filename, dst_prefix):
 -    prefixes = [sys.prefix]
 -
--    if sys.platform == "darwin":
+-    if is_darwin:
 -        prefixes.extend((
 -            os.path.join("/Library/Python", sys.version[:3], "site-packages"),
 -            os.path.join(sys.prefix, "Extras", "lib", "python"),
--            os.path.join("~", "Library", "Python", sys.version[:3], "site-packages")))
+-            os.path.join("~", "Library", "Python", sys.version[:3], "site-packages"),
+-            # Python 2.6 no-frameworks
+-            os.path.join("~", ".local", "lib","python", sys.version[:3], "site-packages"),
+-            # System Python 2.7 on OSX Mountain Lion
+-            os.path.join("~", "Library", "Python", sys.version[:3], "lib", "python", "site-packages")))
 +    prefixes = ["/nix/store", sys.prefix]
  
      if hasattr(sys, 'real_prefix'):
          prefixes.append(sys.real_prefix)
-@@ -968,6 +962,8 @@
-             _, relpath = filename.split(src_prefix, 1)
-             assert relpath[0] == os.sep
-             relpath = relpath[1:]
-+            if src_prefix == "/nix/store":
-+                relpath = "/".join(relpath.split("/")[1:])
+@@ -1162,6 +1152,8 @@
+             if src_prefix != os.sep: # sys.prefix == "/"
+                 assert relpath[0] == os.sep
+                 relpath = relpath[1:]
++                if src_prefix == "/nix/store":
++                    relpath = "/".join(relpath.split("/")[1:])
              return join(dst_prefix, relpath)
      assert False, "Filename %s does not start with any of these prefixes: %s" % \
          (filename, prefixes)
diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index e2f75b5ce63f..07176ad782eb 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -3076,10 +3076,10 @@ let pythonPackages = python.modules // rec {
   });
 
   virtualenv = buildPythonPackage rec {
-    name = "virtualenv-1.6.4";
+    name = "virtualenv-1.8.4";
     src = fetchurl {
       url = "http://pypi.python.org/packages/source/v/virtualenv/${name}.tar.gz";
-      md5 = "1072b66d53c24e019a8f1304ac9d9fc5";
+      md5 = "1c7e56a7f895b2e71558f96e365ee7a7";
     };
 
     patches = [ ../development/python-modules/virtualenv-change-prefix.patch ];