Akona and Odwa played together for Border and South Africa 'A' before joining different Super 14 teams - Akona went to the Bulls and Odwa the Sharks.
It was Akona who made the grade first with the Springboks, making his debut against Australia in the Tri-Nations in 2006, and now Odwa will join him among the international ranks when he lines-up against Italy in Cape Town. The 27-year-old Akona currently has nine caps, and two Test tries, to his credit.
"It is special, not only for me, but for the whole family. I have spoken to Akona and he has been very supportive and is also looking forward to seeing me getting my first cap," said Odwa.
"Akona just told me that I mustn't try to prove a point. He said that I must do what I did that got me here and that has taken some of the pressure off.
"I have been playing well for quite a while now and been looking forward to getting my first cap. I hope to put up my hand for Tri-Nations and do well there also.
"I had faith. I believe in my abilities and I have been working hard, so now it has paid off."
As to which one of the twins is the better player, Odwa neatly sidesteps that argument.
"People are entitled to their own opinions. Akona definitely deserved his chance when he got it and now I am very grateful for the opportunity given to me," he said.
The Ndungane's become the 32nd set of brothers to play for South Africa, but the fact they are twins makes them a pretty rare breed on the international stage.
The first set of twins to play international rugby in the same team were the Camel brothers from Toulouse. They were in the French team against Wales in 1929.
The Scottish back row players Jim and Finlay Calder hold the distinction of being twins who have played for both their country and the Lions. Jim toured New Zealand in 1983 with the Lions, playing in one Test, while Finlay was captain of the victorious 1989 tour party in Australia.
The Whetton twins, Alan and Gary, were the first set of twins to play for New Zealand and they were both in the All Blacks sides that won the inaugural Rugby World Cup in 1987.
The Ella brothers, Glen and Mark, both played for the Wallabies, while more recently Manuel and Felipe Contepomi, of Argentina, and Dan and Mike Pletch (Canada) played in the 2007 Rugby World Cup.