Issue #3696: Error parsing arguments on OpenBSD <= 4.4 and Cygwin.

Patch by Amaury Forgeot d'Arc, reviewed by me.
diff --git a/Misc/NEWS b/Misc/NEWS
index b1aafac..111450d 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,11 @@
 Core and Builtins
 -----------------
 
+- Issue #3696: Error parsing arguments on OpenBSD <= 4.4 and Cygwin. On
+  these systems, the mbstowcs() function is slightly buggy and must be
+  replaced with strlen() for the purpose of counting of number of wide
+  characters needed to represent the multi-byte character string.
+
 - Issue #3697: "Fatal Python error: Cannot recover from stack overflow"
   could be easily encountered under Windows in debug mode when exercising
   the recursion limit checking code, due to bogus handling of recursion