Look in your camera menu and see if there is a pixel mapping
function. If so, use it and that should fix it. They expect the odd bad one to appear occasionally so have the ability to map it out.
There is another related possibility. Was the exposure a particularly long one? Say over a second? That also tends to amplify any noise of the sensor even when there isn't a specific fault as such. In this scenario cameras may offer a long duration noise reduction to reduce this effect.
Both the above options are available on my Olympus E-510 and Sony A350 so I'd expect it to be available on most if not all DSLRs.