phpseclib给了我一个奇怪的错误

Warning: include_once(Math/BigInteger.php): failed to open stream: No
such file or directory in
/home/www/sfs_web/statistics/_public/_functions/Server/Net/SSH2.php on
line 891

Warning: include_once(): Failed opening ‘Math/BigInteger.php’ for
inclusion (include_path=’.:/usr/share/php:/usr/share/pear’) in
/home/www/sfs_web/statistics/_public/_functions/Server/Net/SSH2.php on
line 891

Warning: include_once(Crypt/Random.php): failed to open stream: No
such file or directory in
/home/www/sfs_web/statistics/_public/_functions/Server/Net/SSH2.php on
line 895

Warning: include_once(): Failed opening ‘Crypt/Random.php’ for
inclusion (include_path=’.:/usr/share/php:/usr/share/pear’) in
/home/www/sfs_web/statistics/_public/_functions/Server/Net/SSH2.php on
line 895

Warning: include_once(Crypt/Hash.php): failed to open stream: No such
file or directory in
/home/www/sfs_web/statistics/_public/_functions/Server/Net/SSH2.php on
line 899

Warning: include_once(): Failed opening ‘Crypt/Hash.php’ for inclusion
(include_path=’.:/usr/share/php:/usr/share/pear’) in
/home/www/sfs_web/statistics/_public/_functions/Server/Net/SSH2.php on
line 899

Warning: include_once(Crypt/Base.php): failed to open stream: No such
file or directory in
/home/www/sfs_web/statistics/_public/_functions/Server/Net/SSH2.php on
line 904

Warning: include_once(): Failed opening ‘Crypt/Base.php’ for inclusion
(include_path=’.:/usr/share/php:/usr/share/pear’) in
/home/www/sfs_web/statistics/_public/_functions/Server/Net/SSH2.php on
line 904

Fatal error: Call to undefined function
phpseclib_resolve_include_path() in
/home/www/sfs_web/statistics/_public/_functions/Server/Net/SSH2.php on
line 1226

include('Net/SSH2.php');
$ssh = new Net_SSH2('host');
if (!$ssh->login('user','pass')) {
  echo('Login Failed');
}

$ssh->exec('the cmd line...");
$ssh->disconnect();