Free Backwpup not working on Multisites?

I’ve just created a Multisite-Environment with Multilingual Press and moved the old site there. Now when I wanted to create backup jobs, I can create them, but after I’ve saved them, the jobs list is still empty. AFAIK I can only enable Backwpup at the root level not for individual blogs, right? So I wonder if the free version supports Multisite Environments?

http://wordpress.org/plugins/backwpup/