Nope, it's quite real. From his interview for a New Yorker article:
http://www.freerepublic.com/focus/f-chat/980753/posts
The part where he explains why his wife is going to hell is near the end.
I don't get why so many FReepers stubbornly refuse to believe that this guy is a complete lunatic.
Interview with Hutton Gibson:
http://www.moviecitynews.com/notepad/2004/040303_npd.html
Mel financing a church for his father:
http://www.pittsburghlive.com/x/pittsburghtrib/s_416937.html
NYT Magazine article:
http://www.rickross.com/reference/general/general534.html