Package: x2goclient

When I started X2Go I got a popup saying

"Unable to find the sftp-server binary. Neither bundled, nor found in $PATH nor additional directories.
If you are using a Linux-based operating system, please ask your system administrator to install the package containing the sftp-server binary. Common names are openssh, openssh-server or openssh-sftp-server depending upon distribution.
If the sftp-server binary is installed on your system, please report a bug mentioning its path on:"

I went searching on what this could mean. I found

"Overview of third-party components
X2Go Client for Windows needs several 3rd-party programs for being able to run on MS Windows: nxproxy OpenSSH Server for file sharing (optional) "

So OpenSSH Server is optional and thus I presume the sftp-server is also. So why do I get the messeage stating that I need a sftp-server? Shouldn't
1. at least the text be changed?
2. a checkbox added to silence this message?

When I close the popup (Hit the OK button of it) the whole X2Go client closes. So in order to use the X2Go client I have to leave the popup window opened. That is a bit annoying.

Thanks for X2Go. I like it.

With kind regards,