For 3gs users who have experienced reboots during phone calls.
This seems to be a problem that has been effecting many phones since the upgrade to OS 4.0 including mine.
If you are suffering such problems it is very much in your interest to get your phone to Apple whilst still in its warranty. There is a suggestion that it affects a particular batch of phones and those who have got replacements from Apple now have no problems.
This thread click here has been running for many months and is over 139 pages long.