Merged revisions 71875 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

........
  r71875 | walter.doerwald | 2009-04-25 14:15:07 +0200 (Sa, 25 Apr 2009) | 7 lines

  Issue #5837: Certain sequences of calls to set() and unset() for
  support.EnvironmentVarGuard objects restored the environment variables
  incorrectly on __exit__.

  Fix this by recording the initial value of each environment variable on the
  first access in set() or unset().
........
diff --git a/Misc/NEWS b/Misc/NEWS
index 5c074e1..fdaf081 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -32,6 +32,13 @@
   dispatcher now has an 'ignore_log_types' attribute for suppressing
   log messages, which is set to 'warning' by default.
 
+Tests
+-----
+
+- Issue #5837: Certain sequences of calls to set() and unset() for
+  support.EnvironmentVarGuard objects restored the environment variables
+  incorrectly on __exit__.
+
 
 What's New in Python 2.6.2 rc 1
 ===============================