i18n by python不能在web上工作

Question

1. “cn”和“en”都在终端中工作
2. “en”适用于网络，但“cn”不起作用;

如何让“cn”在网络上运作？

BTW：msgfmt，Fedora18，httpd;

test.py：

#!/usr/bin/env python
# -*- coding: utf-8 -*-
import gettext
gettext.install('lang', './locale', unicode=True)
gettext.translation('lang', './locale', languages=['cn']).install(True)

print "Content-type: text/plain\n" 
print _("Hello world!")
print "中文"

终端输出“cn”：

[root@localhost cgi-bin]# ./test.py 
Content-type: text/plain

中文

“en”终端输出：

[root@localhost cgi-bin]# ./test.py 
Content-type: text/plain

It works.
中文

网页“en”：

It works.
中文

网页“cn”： 什么都不显示

“curl locahost / cgi-bin / test.py”by“cn”： 什么都不返回

区域设置/ CN / LC_MESSAGES / lang.po：

# SOME DESCRIPTIVE TITLE.
# Copyright (C) YEAR ORGANIZATION
# FIRST AUTHOR <EMAIL@ADDRESS>, YEAR.
#
msgid ""
msgstr ""
"Project-Id-Version: PACKAGE VERSION\n"
"POT-Creation-Date: 2013-08-12 05:20+EDT\n"
"PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
"Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
"Language-Team: LANGUAGE <LL@li.org>\n"
"MIME-Version: 1.0\n"
"Content-Type: text/plain; charset=UTF-8\n"
"Content-Transfer-Encoding: utf-8\n"
"Generated-By: pygettext.py 1.5\n"

msgid "Hello world!"
msgstr "你好！"

区域设置/ EN / LC_MESSAGES / lang.po：

# SOME DESCRIPTIVE TITLE.
# Copyright (C) YEAR ORGANIZATION
# FIRST AUTHOR <EMAIL@ADDRESS>, YEAR.
#
msgid ""
msgstr ""
"Project-Id-Version: PACKAGE VERSION\n"
"POT-Creation-Date: 2013-08-12 05:20+EDT\n"
"PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
"Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
"Language-Team: LANGUAGE <LL@li.org>\n"
"MIME-Version: 1.0\n"
"Content-Type: text/plain; charset=UTF-8\n"
"Content-Transfer-Encoding: utf-8\n"
"Generated-By: pygettext.py 1.5\n"

msgid "Hello world!"
msgstr "It works."

路径：

/var/www/cgi-bin/
|-- locale
|   |-- cn
|   |   `-- LC_MESSAGES
|   |       |-- lang.mo
|   |       `-- lang.po
|   `-- en
|       `-- LC_MESSAGES
|           |-- lang.mo
|           `-- lang.po
`-- test.py