WordPress MU

Is there a plugin so i can share google adsense space with the bloggers? I found and tested a couple plugins.
(I don't have and want to use the widget plugin) <-- that is the first problem. Some plugins need widget.

2nd. Not all the plugins builders read the Adsense TOS (it's a shame ;) I don't want to lose my Adsense account because of a crappy plugin. What i try to say is that i want to use more than 1 ad per/page, but some plugins will calculate the % not by IP or something, so there will be more than 1 Adsense ID per/page (not good at all)

And i want to be able to show my own Adsense ads if the blogger is not using a Adsense id (not activating the plugin)

BIG THANKS ;)

Hand code your adsense script into each sidebar file using your id. If your users choose to use the sidebar based plugin then it will get rid of your adsense bar.
Having a plugin overwrite another plugin isn't something I'm sure would be easy to do. Although I suppose if the plugin activatable by the user were to do a function check to block your default plugin you could do it.