As stated in modules/system/system.module "SSH2 lib connection is only available if the proper PHP extension is installed". Using phpseclib would eliminate that requirement. It has a number of advantages over libssh2:

http://phpseclib.sourceforge.net/ssh/compare.html

There's a php5 branch that uses more modern design paradigms than the master branch but it is a work in progress.

Rather than rewrite includes/filetransfer/ssh.inc this could be used:

https://github.com/phpseclib/libssh2-compatibility-layer

Just a two second change and ssh2 is available for everyone.

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Version: 7.28 » 7.x-dev

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