This commit makes the parser and lexer use regular string comparison to support jython

--HG--
branch : trunk
diff --git a/jinja2/defaults.py b/jinja2/defaults.py
index aacd32b..b1a2f6a 100644
--- a/jinja2/defaults.py
+++ b/jinja2/defaults.py
@@ -36,4 +36,4 @@
 
 
 # export all constants
-__all__ = tuple(x for x in locals() if x.isupper())
+__all__ = tuple(x for x in locals().keys() if x.isupper())