I have some code I need to write a test for that connects to a vendor's SFTP server and puts a file there. Right now the test is connecting to their actual server but I'd rather not do that. Ideally I'd like to use a fake, in memory, sever along the lines of [MockFtpServer](http://mockftpserver.sourceforge.net/). The I tried using that one and it gets part of the way there but dies at the point of issuing the actual commands since it doesn't recognize them.

The code in question is a flow setup within [Mule ESB](http://www.mulesoft.org/).