Australian Greens Leader Bob Brown has rebuffed Cardinal Pell's Easter attack on the Greens as not very Christian.

"I hope the good Cardinal reads The Australian's Easter editorial noting comments from Melbourne's Catholic Archbishop Denis Hart and calling for ‘forgiveness, atonement, hope, tolerance and generosity'. Somewhere up the Hume Highway as you get towards Archbishop Pell these sound religious values tend to evaporate," Senator Brown said today in Hobart.

Australian Greens leader, Senator Bob Brown, joins Senator Larissa Waters and Queensland Greens lead candidate Adam Stone to speak to the media about the the Greens holding their own in the Queensland elections.

The full text of Bob's speech is below:

The Gillard and Giddings governments should move to extend the Tasmanian Wilderness World Heritage Area to include forests in the Tarkine, Styx, Weld, upper Florentine and Great Western Tiers, Australian Greens Leader Bob Brown said today.

"The report by Professor Jonathan West and his team of experts has backed what the Greens have been saying for 20 years - that Tasmania's giant eucalypts and rainforests are of World Heritage value," Senator Bob Brown said.

"The report says that this could be our 'last chance' to protect the heritage values of these forests.

Australian Greens Leader Bob Brown today called in the Senate for the leadership of the Liberal and National parties to disassociate themselves from the defamatory claims made by billionaire Clive Palmer against the Queensland Greens candidates for Saturday's election.

"Clive Palmer, one of the Liberal and National parties' largest donors, has made untrue claims aimed at damaging the Greens three days out from the election. Tony Abbott and Campbell Newman have failed to disassociate themselves from the false remarks made by Mr Palmer," Senator Brown said.

The claims by Coalition Senator Kroger against Australian Greens Leader Bob Brown and Deputy Leader Christine Milne, referred to the Senate's powerful Committee of Privileges, have been thrown out as having "no cogent evidence".

Similarly, the committee found Senator Kroger had no evidence for her claims against Mr Graeme Wood and that "no question of contempt arises". These findings were unanimous.

The claims, if proven, had opened the Senators to a sentence of six months in jail.

Hobart Town Hall has claim to be the birthplace of Green politics worldwide. The 40th anniversary of the first Greens meeting in the world will be celebrated there this Friday night, 23rd March.

Australian Greens Leader Bob Brown will give the third Green Oration, on global democracy. The debut of his Song of the Earth, sung by Cygnet mezzo soprano Claire Dawson aka SiSi, will also feature Rod Thomson playing the Town Hall organ.

The Tasmanian Greens will celebrate their 40th birthday on March 23rd 2012 in the Hobart Town Hall exactly 40 years after the world's first Greens Party meeting - a tumultuous affair - on March 23rd 1972.

Australian Greens Leader Senator Bob Brown will give the annual Green Oration. He will be outlining his vision for the future of the Greens and Global Democracy.