I jump curbs all the time with panniers. You just need to make sure they're secure.

Curb jumping also depends on your bike, tires, and wheels. I ride a Salsa La Cruz (cyclocross bike) with 700x32c tires...I keep the front around 90 PSI and the rear around 75-80 PSI (just so it's a little more squishy). Although most road wheels (if properly tensioned) can take tons of curbs, I have 29er MTB wheels (Stan's Arches) because I'm bigger--about 240ish with my panniers/gear--and don't want to worry about bending a rim out of shape.

To hop a curb, I slow down, do a wheelie with my front wheel and roll over with my rear wheel. I wouldn't suggest hitting a curb at a speed though.

If you're on a MTB with front suspension, curbs should be no problem. I wouldn't worry at all about hopping curbs, especially with such high volume tires. If the curbs are as big as you say though, just make sure that your bike can clear them without bashing your chainrings on concrete.