What needs to be done to repair a digital odomoter incorrect display?

The digital display on my car's odometer is not displaying numeric values. Is this an expensive repair? Is the mileage still being captured correctly on the car? This is for a 2000 Mazda 626. This problem has coincided with a problem I am experiencing with the dashboard light not staying on. I am guessing it has some sort of short in it. It seems to go on and off at will.