From what you say, it seems you are one of the administrators there. Maybe you are in charge of one of the domains in your tree, or an organisational unit. You want to know how to let the boss know how grave the situation is?
Hack him/her... not maliciously, but as an eye opener. Get an annonymous account from one of the free providers, and send him a mail, with an attachment containing one of his private documents. Then he/she'll understand the situation and act accordingly.
In the company where I was an intern, each person had full control over his/her computer with local accounts, with the exception of when they needed to use domain resources like printers and remote storage.
Another thing you could do is to put up a firewall that will prevent the corporate admin from getting into your computer. I have one on my pc from Zonelabs. Even if I'm logged onto the domain, the admin can't get into my computer without me knowing and either permitting or denying access.
Hope this helps in a way, though it's a very "youthful" advice, and risky as well.
God blesss you!