安裝xcache是出現：
[root@master xcache-3.0.4]# /usr/local/php/bin/phpize
Configuring for:
PHP Api Version: 20121113
Zend Module Api No: 20121212
Zend Extension Api No: 220121212
Cannot find autoconf. Please check your autoconf installation and the
$PHP_AUTOCONF environment variable. Then, rerun this script.
解決方法：
yum install m4* autoconf*