If he has had a massive stroke which the press has reported, then there is no way he will be back at work. He will need to recover use of whichever part of him has been affected, down one side and speech are the usual!
Its sad cause i love his character and he seems a nice chap too. He was great fun when he appaeared on the two of us.
Not sure how they will write him out Norm but i bet it gives the scriptwriters a bit of a headache.