Webshell5 is not working on CentOS 6.
> [error] [client 10.10.10.10] script not found or unable to stat: /hsphere/shared/php4
WebShell 5 requires the end-of-life PHP 4, which is not supported by these operating systems.
Customer sites must use WebShell 4. See H-Sphere 3.6 Release Notes: http://download.hsphere.parallels.com/release_notes/3.6.0/