diff --git a/Lib/test/test_support.py b/Lib/test/test_support.py
index 948c64561f8..c720f433629 100644
--- a/Lib/test/test_support.py
+++ b/Lib/test/test_support.py
@@ -81,6 +81,8 @@ def fcmp(x, y): # fuzzy comparison function
 except NameError:
     have_unicode = 0
 
+is_jython = sys.platform.startswith('java')
+
 import os
 # Filename used for testing
 if os.name == 'java':