I still think it's in rather poor taste, when Justin Lee Collins holds aloft a false arm and claims it belongs to Jade's mum, or Charlotte Church raises a false leg and says it belongs to Heather Mills.

I don't think they'd normally do gags about the physically handicapped, but if the person in question is a celebrity or featured in the news , then they're "fair game".

In those instances are they not more mocking the celebrity rather than the handicap in general?
They couldnt be mocking two nicer people eh?

I'm disabled and I mock myself. I don't find it offensive one bit!

It is a bit of a cheap gag and I'm sure some people will find it offensive but you can't please everyone all the time.
I get the mick takin out of me all the time due to my disability, no big deal.