diff --git a/CHANGES.rst b/CHANGES.rst
index 3d8e71e..cee1a56 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -1,6 +1,11 @@
 Changelog
 =========
 
+UNRELEASED
+~~~~~~~~~~
+
+- Fix an issue where loading a thrift file in a sub-thread will cause an error.
+
 0.5.0
 ~~~~~
 
diff --git a/thriftpy2/__init__.py b/thriftpy2/__init__.py
index eadf440..ef58495 100644
--- a/thriftpy2/__init__.py
+++ b/thriftpy2/__init__.py
@@ -5,7 +5,7 @@
 from .hook import install_import_hook, remove_import_hook
 from .parser import load, load_module, load_fp
 
-__version__ = '0.5.0'
+__version__ = '0.5.1rc1'
 __python__ = sys.version_info
 __all__ = ["install_import_hook", "remove_import_hook", "load", "load_module",
            "load_fp"]