WPMU compatible

Is there a simple hack to make this work on a multisite?

I’m just trying to disable access temporarily to our users for some server updates.

It works great on a site-by-site basis, it’s just a pain to go through all the sites to activate and configure.

TIA!

http://wordpress.org/plugins/remove-dashboard-access-for-non-admins/