Meh, I think Senju can control both bijuu and jinchuriki, because jinchuriki are sealed in different ways, and they'd have to have different techniques to supress bijuus sealed in different ways. It seems they simply supress the chakra of bijuu, which would, theoretically, affect bijuu.
ALSO, guys. In the picture of the shodaime vs. madara battle, I don't have it handy, where it shows the 9-tails, there is a little wood grasping one of its tails. I think that could be shodaime preparing to do the bijuu supressant jutsu.