I would give him plenty of fluids, calpol and see how he gets on. It will be grim waiting around in A&E for hours only to be told to give him calpol and fluids. If he's still feeding and seems well enough then he'll probably be fine just keep a close eye on him.
I agree with kidcreole. They wont see it as an issue at the hospital unless DS is showing other signs of distress i.e. floppy and listless and/or wont take fluids - because dehydration is a worry.
He sounds fine at the moment. Please dont panic yet - he will probably hit that temp many times over the course of babyhood I know mine has! Just monitor, make sure he's getting fluids down him and keep attempting the calpol!
Thanks all, he seems okay at the moment, quite snoozy, but still feeding like a good 'un.
I blame my mother for me even wondering about it. Until the Swine flu epidemic, I only had a forehead thermometer, so only ever knew DD's temp when she was a baby very very vaguely. Then DM turned up with a digital one so now I can check her and DS to the 0.01 degree, and I'm much more of a worrier. Panic-merchant!