Jenkins/Hudson Testlink Plugin usage

[Darek]

Hi guys.
I've updated my Testlink plugin in Jenkins to v2.2.2
Now I can see new textarea named "Single test command" with description
"This command when present will be executed before the plug-in iterates the retrieved automated test cases. It is useful when you have a set of automated test cases and a single test command that executes a test suite, for instance."

Does somebody use this field to run TestNG test suite? How can I do that? What environment variables can I use?

Thank you.