Sceptics said it would never last. As promising as the new dawn in northern Irish politics appeared earlier this year, could Ian Paisley really keep up his astonishing transformation from hardline Unionist to cheerful, co-operative colleague of lifelong republican enemies?

More than six months on, his critics appear to have been confounded. Radiating goodwill and an unanticipated talent for give-and-take, the man formerly known as "Dr No" has been saying an unreserved "yes" to a whole host of people and places that he would once have roundly denounced, extending the hand of friendship to Irish nationalists and senior Catholic figures alike.

His latest declaration of love, however, has prompted even his keenest of supporters to wonder how far Northern Ireland's First Minister will go to demonstrate his sensitive side. Speaking at Stormont at the heavily publicised launch of the autobiography of Dana, the former Eurovision song contest winner who has become as much a symbol of Catholic fundamentalism as Mr Paisley has been for fundamentalist Protestantism, he raised eyebrows by showering the singer with praise and even describing her as "a woman of great faith". In his fiery, younger days he would have been more likely to shun her as a woman of the profoundly wrong faith.

But in this era of fresh hope, he added: "We are proud, no matter what part of Northern Ireland or southern Ireland we come from, that she is a person from this island and part of ourselves, and we hail her as a woman supreme." He recalled listening to Dana singing "All Kinds of Everything" in 1970 and remarking to his mother, "Mammy, that lady can sing".

As his grins and guffaws at the book launch illustrated, Mr Paisley has thrown himself into his new role with all the larger-than-life gusto he once devoted to chastising exactly this kind of bridge-building activity. Fire and brimstone have been replaced by sweetness and light and, what's more, it does not even appear to be an effort for him: after years as a rebellious outsider, he is clearly enjoying his new status at the top of Belfast's political tree. He is now a regular, and willing, visitor to Dublin, which he once avoided. He has met the Irish President, Mary McAleese, and is in regular contact with the Irish Prime Minister, Bertie Ahern. He has even had cordial discussions with the head of the Catholic church.

Some have wondered if all this was a bit unnatural for the one-time hammer of Catholicism, republicanism and nationalism. They have been waiting to see whether an old-style eruption of Mount Paisley might occur.

But no: he now revels in agreement and reconciliation, proudly boasting that the multi-party executive he chairs has considered 105 items of business, and failed to attain full consensus on only three occasions.

Next month he is off to the US with Martin McGuinness to push for investment. The Paisley-McGuinness relationship is the most striking of all: they get on so well, sharing jokes together in public so often, that they have been tagged "the Chuckle Brothers".

According to the Sinn Fein leader there has "not been one angry word" between them over the past six months: instead, they have "a cordial, civilised, positive working relationship" although for most of their lives, as he put it, they had "detested" each other. The republican added: "He clearly showed himself to be someone who, along with the rest of us, had crossed the Rubicon. We are now in a new world." Belfast is certainly revelling in a new political world, complete with a new Ian Paisley.

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