سلام

بعد از اجرای دستور پیغام زیر رو میده

کد:
[root@server local]# /usr/local/php5/bin/pecl install json
WARNING: channel "pear.php.net" has updated its protocols, use "pecl
channel-update pear.php.net" to update
downloading json-1.2.1.tgz ...
Starting to download json-1.2.1.tgz (17,780 bytes)
......done: 17,780 bytes
11 source files, building
WARNING: php_bin /usr/local/php5/bin/php appears to have a suffix 5/b
in/php, but config variable php_suffix does not match
running: phpize
Configuring for:
PHP Api Version:         20041225
Zend Module Api No:      20060613
Zend Extension Api No:   220060519
Cannot find autoconf. Please check your autoconf installation and the
$PHP_AUTOCONF environment variable. Then, rerun this script.

ERROR: `phpize' failed
قسمت اول که ظاهرا میگه باید دستور زیر رو بزنم:
کد:
pecl
channel-update pear.php.net
ارور قسمت دوم چیه؟