Added 'boolean_options' list to support config file parsing.
diff --git a/Lib/distutils/command/clean.py b/Lib/distutils/command/clean.py
index 2f3597f..4f04f08 100644
--- a/Lib/distutils/command/clean.py
+++ b/Lib/distutils/command/clean.py
@@ -28,6 +28,8 @@
          "remove all build output, not just temporary by-products")
     ]
 
+    boolean_options = ['all']
+
     def initialize_options(self):
         self.build_base = None
         self.build_lib = None