Gradle : How to apply Source Properties?

Hello Guys,
Me and a friend are using Gradle + mercurial to make a libgdx project.
And he uses eclipses and i use netbeans.
Everything was great until my netbeans started to see the main folder as a package… And now is bugging everything.

Normally java projects have the option to change the source folder directory.
Gradle doesnt have it? At least in my netbeans properties.

I need help.
How do i change the directory of the source folder in gradle?

Im using the NB plugin of course.

Thanks in advance.