Correctional Services said that “matters are under control” at Johannesburg’s Sun City Prison on Wed.
Demonstrations at the Swaziland embassy in Pretoria and pressure put on South African soccer players and artists not to take part in the Swaziland celebrations on Saturday achieved very little.
And the South African government says it will not be swayed by growing calls for it to boycott the oppressive Swazi regime.
The Young Communist League, Cosatu and ANC Youth League were campaigning against South Africans taking part in the 40-40 Swaziland celebration.
Foreign Affairs spokesman Ronnie Mamoepa said the government had not discussed the isolation of Swaziland.
"The issue of sport or cultural boycott has not been discussed by government," Mamoepa said.
The SA Football Association and several artists were billed to take part in the dual celebrations marking King Mswati's 40th birthday and the country's 40th independence celebrations.
Throughout last week pressure was put on them not to honour the engagements.
Cosatu said it would stage a week-long boycott of goods destined for Zimbabwe and Swaziland this month.
The Swaziland Solidarity Network said it would intensify its demand for democracy through strikes and marches against the regime. The network demands multiparty elections that are set to be held later this month, a R500 a month grant for the elderly and adherence to international treaties to which the nation is party.
Sapa reports that the king attended the dual celebrations in lavish style on Saturday. He toured the stadium in an open-topped BMW to cheers and fluttering flags.
The loudest cheer was reserved for Zimbabwean President Robert Mugabe, popular in the region because he is seen as standing up to to the West.
Mswati is Africa's last absolute monarch. He is widely revered, but there is anger about his and his 13 wives' luxurious lifestyle.