[Help] Wordpress MS (MU) changing all the sites theme

Hi,

I have a blog network of about 1000+ sites using Wordpress MS (MU I guess it used to be called). I am not too familiar with it, I am just playing around with it, so I am not sure if the following can be done.

I want to change every sites theme to another one. I just want to update all of the 1000 sites across the board at once to another theme (Same theme on each site). Does anyone know if this can be done? All in one go, not having to go to each site and press edit or something...?

Also, does anyone know how I would activate plugins for EACH site?

Thanks for your help -- I have tried searching Google for the same, but I guess my terminology or wording isn't correct.

Thanks!

Okay - Thanks for the people who PMed me...

I actually figured this one out on my own.. After searching and searching, I found a plugin that does what I want it to...

The plugin is: YD-WPMU-Sitewide-Options or you can find it here:
http://www.yann.com/en/wp-plugins/yd-wpmu-sitewide-options

What it does, is it replicates what you want (plugins, themes, etc...) on the domain.com blog and puts it on the domain.com/blog1 domain.com/blog2, etc... blogs...

So hopefully this will help someone in the future... Thanks everyone!

Take it easy