Oh dear, the Politically Correct wankers are at it again.
Comments that are taken to the Nth degree like claimed by that Jasper guy that a joke suddenly becomes schoolyard taunts and racist slurs is just rubbish, particulary in this PC world, as people are a lot better educated these days, and fully aware pigeonholing people is just not on.
Now of course if he'd called Lenny Henry a "dirty black c**t" or similar plain derogatory targetted at him, then that's a whole lot different.