Sean Penn directly challenged homophobia in his acceptance speech at the Academy Awards last night.

Mr Penn won Best Actor for his portrayal of Harvey Milk, the first openly gay man to be elected to public office in the US.

He was assassinated in 1978, less than a year after being elected to the San Francisco Board of Supervisors.

The Oscars ceremony was targeted by homophobic Christian groups. Some held up placards claiming actor Heath Ledger, who died last year, is in Hell. Mr Ledger was named Best Supporting Actor for his performance in The Dark Knight.

“Thank you. Thank you. You commie, homo-loving sons-of-guns,” Mr Penn said when accepting his Oscar at last night’s 81st Academy Awards.

“I did not expect this, but I, and I want it to be very clear, that I do know how hard I make it to appreciate me often.

“But I am touched by the appreciation and I hoped for it enough that I did want to scribble down, so I had the names in case you were commie, homo-loving sons-of-guns, and so I want to thank my best friend, Sata Matsuzawa.

“My circle of long-time support, Mara, Brian, Barry and Bob. The great Cleve Jones. Our wonderful writer, Lance Black. Producers Bruce Cohen and Dan Jinks.

“And particularly, as all, as actors know, our director either has the patience, talent and restraint to grant us a voice or they don’t, and it goes from the beginning of the meeting, through the cutting room. And there is no finer hands to be in than Gus Van Sant.

“And finally, for those, two last finallies, for those who saw the signs of hatred as our cars drove in tonight, I think that it is a good time for those who voted for the ban against gay marriage to sit and reflect and anticipate their great shame and the shame in their grandchildren’s eyes if they continue that way of support.

“We’ve got to have equal rights for everyone. And there are, and there are, these last two things. I’m very, very proud to live in a country that is willing to elect an elegant man President and a country who, for all its toughness, creates courageous artists.

“And this is in great due respect to all the nominees, but courageous artists, who despite a sensitivity that sometimes has brought enormous challenge, Mickey Rourke rises again and he is my brother. Thank you all very much.”