diff --git a/SCons/Config/ms b/SCons/Config/ms
index ecd9548a..0e76b7a7 100644
--- a/SCons/Config/ms
+++ b/SCons/Config/ms
@@ -6,6 +6,8 @@ Import('defenv')
 
 import SCons
 if SCons.__version__ == '1.3.0':
+  # workaround for http://scons.tigris.org/issues/show_bug.cgi?id=2614
+  # force inclusion of Platform SDK, sometimes ignored by SCons 1.3.0 due to environment contamination
   defenv.Tool('mssdk')
 
 defenv['ENTRY_FLAG'] = lambda x: '/entry:' + x