Oh dear. First problem, and it's a good one.

I bought the Omega last week, (2003 2.6 CDX auto). Since then I've been a bit busy, and as I was waiting for my Trade Card to turn up, didn't really have any need to enter or move the car.
Well, I've just gone out now to have a look at the mileage, and I can't get the bloody thing to open.
The battery in the key fob is flat, and was when I bought it. This wasn't really a problem as I could lock / unlock it by just using the key. Also I suspected that the car battery was on it's last legs as well.
So, I've just gone out to the car, put the key in the door lock and turned it, and nothing. Tried turning the key through 180 degrees and tried again but nothing. :-?
I can't see how replacing the battery in the key fob will make any differance if the car battery is flat as well. So besides smashing the glass, do any of you chaps have any other suggestions or ideas on how to unlock the car? Obviously I can't open the bonnet to jump start the car, as I cant open the car to get to the bonnet release.
Help please?