nixpkgs/pkgs/development/libraries/serf/scons.patch

diff --git a/SConstruct b/SConstruct
index 4358a23..0d862e7 100644
--- a/SConstruct
+++ b/SConstruct
@@ -155,6 +155,7 @@ if sys.platform == 'win32':
 env = Environment(variables=opts,
                   tools=('default', 'textfile',),
                   CPPPATH=['.', ],
+                  ENV=os.environ,
                   )
 
 env.Append(BUILDERS = {