似乎在某些系统上，setlocale()不够.

Seems to be that on some systems setlocale() isn't enough.

http://nl3.php.net/manual/en/function. gettext.php

对于某些系统和putenv()而言，设置语言是不够的 应该用于定义当前语言环境.

Setting a language isn't enough for some systems and the putenv() should be used to define the current locale.

我添加时问题已解决:

putenv('LC_ALL=0');