php中的Fatal error: Call to undefined function ssh2_connect()问题！！！

在win7下架起了mysql+apache+php环境，现在想要用php通过ssh在远端服务器上执行命令，参考网上教程在php.ini内加入extension=php_ssh2.dll， 并将php_ssh2.dll放入ext，extension_dir配置没问题，但就是报错：Fatal error: Call to undefined function ssh2_connect() in D:\phpweb\ssh2\ssh.php on line 2 望各位高手指点一二。

php.ini中的扩展部分：
;extension=php_bz2.dll
extension=php_curl.dll
extension=php_dba.dll
extension=php_dbase.dll
;extension=php_exif.dll
;extension=php_fdf.dll
extension=php_gd2.dll
;extension=php_gettext.dll
;extension=php_gmp.dll
;extension=php_ifx.dll
;extension=php_imap.dll
;extension=php_interbase.dll
extension=php_ldap.dll
;extension=php_mbstring.dll
;extension=php_mcrypt.dll
extension=php_mhash.dll
extension=php_mime_magic.dll
extension=php_ming.dll
extension=php_msql.dll
extension=php_mssql.dll
extension=php_mysql.dll
extension=php_mysqli.dll
;extension=php_oci8.dll
extension=php_openssl.dll
;extension=php_pdo.dll
;extension=php_pdo_firebird.dll
extension=php_pdo_mssql.dll
extension=php_pdo_mysql.dll
;extension=php_pdo_oci.dll
;extension=php_pdo_oci8.dll
;extension=php_pdo_odbc.dll
;extension=php_pdo_pgsql.dll
;extension=php_pdo_sqlite.dll
extension=php_pgsql.dll
;extension=php_pspell.dll
extension=php_shmop.dll
;extension=php_snmp.dll
;extension=php_soap.dll
extension=php_sockets.dll
;extension=php_sqlite.dll
;extension=php_sybase_ct.dll
extension=php_tidy.dll
extension=php_xmlrpc.dll
extension=php_xsl.dll
;extension=php_zip.dll
extension=php_ssh2.dll

php代码如下：
PHP code

<?php
$connection = ssh2_connect('shell.example.com', 22);
ssh2_auth_password($connection, 'username', 'password');

$stream = ssh2_exec($connection, '/usr/local/bin/php -i');
?>

你的host是否配置 shell.example.com这个域名

意思是问你，你电脑能正常访问这个域名吗！