_make_boundary(): Fix for SF bug #745478, broken boundary calculation

in some locales.  This code simplifies the boundary algorithm to use
randint() which is what we wanted anyway.

Bump package version to 2.5.3.

Backport candidate for Python 2.2.3

Lib/email/Generator.py

@@ -5,6 +5,7 @@
 """
 
 import re
+import sys
 import time
 import locale
 import random
@@ -356,11 +357,14 @@ class DecodedGenerator(Generator):
 
 
 # Helper
+_width = len(repr(sys.maxint-1))
+_fmt = '%%0%dd' % _width
+
 def _make_boundary(text=None):
     # Craft a random boundary.  If text is given, ensure that the chosen
     # boundary doesn't appear in the text.
-    dp = locale.localeconv().get('decimal_point', '.')
-    boundary = ('=' * 15) + repr(random.random()).split(dp)[1] + '=='
+    token = random.randint(0, sys.maxint-1)
+    boundary = ('=' * 15) + (_fmt % token) + '=='
     if text is None:
         return boundary
     b = boundary