Current code of execve() has a bug: it uses the length of the environment variable value in *characters* and not in *bytes* to allocate the "p" buffer. I remember that someone wrote a comment somewhere about that... The result is that the environment variable value is truncated by 1 byte.

Example (copy of http://dpaste.com/184803/):
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$ cat test.py
#!/usr/bin/python
# -*- coding: utf-8 -*-

import os

env = {"VAR": "ćd"}
os.execve("test.sh", [], env)
$ cat test.sh
#!/bin/bash

declare -p VAR
$ python2.6 test.py
declare -x VAR="ćd"
$ python3.1 test.py
declare -x VAR="ć"
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