moisture sensors issue for iPhone 3GS?

Hello all,
As I was researching the Iphone 3Gs, I ran across some accounts of users moisture sensors being effected by controls outside of their own actions (i.e, they did nothing unusual, like drop them in water, keep it out in the rain), thus either voiding warranty or messing up the phone.
My most important question is, Does this ('this' meaning moisture sensors go off without provocation) happen often? Is it something I should be concerned about?
Should I not run with my iPhone as sweat might make this happen? I run/bike with my 2gb iPod 3-4 times a week and have for years and have had no issues whatsoever. I was hoping the iPhone would be the same. Please leave comments on your experience regarding the above. Cheers and thanks.
Mountain

I am a contractor and my iphone is always in my pocket,in the summer (both since the iphone came out) it is not uncommon to pull my phone out of my soaking wet pocket or have it covered in sweat during a call. I have never had a problem nor have I heard of the one you have posted.

Hope it helps
Clay

Thanks Clay, I figure with 38 views on the thread so far and no other replies, it is not an issue of concern. Much appreciated, and if anyone else has experience with this, please feel free to comment.

M

I know a guy who left his n the bathroom counter while he took a hot shower and the steam was enough to turn the water sensor pink, Luckily there was no damage to the phone.

Thanks bargsbeer, those are more of the kind of stories I have read as well. Almost more like carelessness by the user then actual issues with design, etc. I have not seen enough solid issues of the kind to back me off the iPhone.

I've had two phones' sensors go bad - both of which never touched water, at Apple I was told they're super sensitive and they're placed in really open places like at the dock at the bottom and in the headphone jack, neither phone had an issue but the warranties did in fact get voided. I would recommend what I did which is get the dock and headphone protectors which are basically plugs that go into the slots to avoid any possible damage that could be done.. Good luck!