Jailed black nationalist leader Nelson Mandela does not believe that the chances of his release have improved despite a recent wave of international appeals for his freedom, his wife said on Saturday.

Winnie Mandela, visiting her husband in Cape Town's Pollsmoor prison for the first time since his 70th birthday on Monday, said Mandela was in very good spirits and "bubbling with hope" for South Africa.Asked if Mandela believed that pleas from all over the world on the occasion of his birthday had improved the prospects of his release, she told reporters:

"Not at all. He did not even mention the subject. It is not a top priority in his political calendar."

Mandela was jailed in 1964 for sabotage and plotting to overthrow white rule in South Africa.