but cant microsoft sue simply on the grounds that they have something patented that is alike to something we use?
No, they can't sue you just because you use something that is "like" what they've patented. Well, they can, but they then have to prove that what you use is EXACTLY[1] what they've patented.
If you're developing a small OSS project, chances are that you might be infringing on a fair number of patents, but nobody is going to bother trying to sue you - You "sell" your product for free, so unless you've got some good support contracts, you've got no money for the patent holder. Of course, when you start talking about a tool as widely used as sudo, somebody might be stupid enough to try and enforce a patent, but in the case of this patent, I believe that such a case would either:
1) Be thrown out because the patent doesn't apply to sudo
2) the case would end in the patent being declared invalid, as there is proof that sudo has existed since 1980, constituing prior art.
I suppose there is always a 3). Linux gets screwed over by stupid judge taking hefty bribes. But let's not dwell on thatand just have some faith in those venerable people passing judgement on the rest of us.
[1] Speak to a patent lawyer for certainty, because this is definately not quite right - right enough for a layman or OSS developer worried about whether he infringes, but if you're trying to make money, yeah, lawyer up and get REAL advise.
This is a very proud and strong statement to make nowadays!
US has 5% of the world's population but 70% of world's lawyers!
It is good not to be hostage of the 'legal' system...
I don't know if not being american is really something to be proud of, I know a fair number of respectable americans. One of them even a lawyer. I'm proud to be able to call myself Australian though, even if some americans have managed to get that confused with Austria.