--- a/src/zc/buildout/easy_install.py	2013-08-27 22:28:40.233718116 +0200
+++ b/src/zc/buildout/easy_install.py   2013-10-07 00:29:31.077413935 +0200
@@ -508,16 +508,31 @@
                         self._dest, os.path.basename(dist.location))
 
                     if os.path.isdir(dist.location):
-                        # we got a directory. It must have been
-                        # obtained locally.  Just copy it.
-                        shutil.copytree(dist.location, newloc)
+                        # Replace links to garbage collected eggs in
+                        # /nix/store
+                        if os.path.islink(newloc):
+                            # It seems necessary to jump through these
+                            # hoops, otherwise we end up in an
+                            # infinite loop because
+                            # self._env.best_match fails to find the dist
+                            os.remove(newloc)
+                            dist = self._fetch(avail, tmp, self._download_cache)
+                            os.symlink(dist.location, newloc)
+                            newdist = pkg_resources.Distribution.from_filename(
+                                newloc)
+                            self._env.add(newdist)
+                            logger.info("Updated link to %s" %dist.location)
+                        # Symlink to the egg in /nix/store
+                        elif not os.path.exists(newloc):
+                            os.symlink(dist.location, newloc)
+                            logger.info("Created link to %s" %dist.location)
                     else:
 
 
                         setuptools.archive_util.unpack_archive(
                             dist.location, newloc)
 
-                    redo_pyc(newloc)
+                        redo_pyc(newloc)
 
                     # Getting the dist from the environment causes the
                     # distribution meta data to be read.  Cloning isn't