diff --git a/setup.py b/setup.py
index ab7909e..f97fbea 100644
--- a/setup.py
+++ b/setup.py
@@ -46,7 +46,7 @@
     """
     Returns True if 'path' can be located in an OSX SDK
     """
-    return path.startswith('/usr/') or path.startswith('/System/')
+    return (path.startswith('/usr/') and not path.startswith('/usr/local')) or path.startswith('/System/')
 
 def find_file(filename, std_dirs, paths):
     """Searches for the directory where a given file is located,
@@ -862,6 +862,7 @@
                         else:
                             if os.path.isdir(dn):
                                 tmp.append(dn)
+                    db_dirs_to_check = tmp
 
                     db_dirs_to_check = tmp