There have always been jokes about death, illness, deformity.... "Did you hear the one about the Christian Brother and the 10-year-old-child....."?
Whether these jokes are acceptible, tastelss, funny... is a matter of judgement, personal taste, sense of humour....
The problems arise when these jokes are used as part of a larger agenda; racism is a pretty common example of how humour can be used to debase and dehumanise in order to persecute a racial, religious, social group.
I might laugh (momentarily) at the Princess Di jokes, but laughing (ie perpetuating) racist jokes is giving centre stage to the holocust perpetrators and apologists - read BNP (thanks but no thanks)
Jim Carroll