Firefox Thinking For Itself??

I'm betting that most of you got the 3.0 update to Firefox as soon as it came out. Heck, the download day was like an Internet holiday and Firefox was proud to destroy all records by having the most downloads of any launched program ever in a single day. Of course, a few of the servers crashed in the process... but that's all history and not really what I wanted to mention.
At work I keep to Firefox version 2. There are a few add-ons I HAVE to have to do my work, and they have not been upgraded to 3 yet.
But this morning when I came into work, other employees and I all noticed that despite configuring the setting to NOT automatically download updates, all our Firefox versions had upgraded to 3. Massive government conspiracy? Evil admins screwing with our settings? Operator error? Let me know if anyone had this happen to them or even could have had it happen to them.