phpseclib，致命错误：找不到类'Net_SSH2'

I already googled for fixes but it seems like it dosent work. I downloaded the 1.0 Version from ther Page, included the Stuff like this:

set_include_path('components/phpseclib');
include('Net/SSH2.php');

Which results in:

 Fatal error: Class 'Net_SSH2' not found in /var/www/web/xxxxx/pages/rootserver.php on line 57

My directory structure is the following

Script: /var/www/web/xxxxx/pages/rootserver.php

Lib: /var/www/web/xxxxx/components/phpseclib

I already tried to put a / or \ infront of Net, more errors as before, still dosent work.

Any idea?