Asked at a news conference if match-fixing was still rife in the game, Smith said, "The anti-corruption unit and the International Cricket Council are doing a great job at monitoring it.
"They communicate with the team frequently. I can only speak for my team, but we have been kept up to date with what they are doing."
Matchfixing has been mentioned in connection with the murder of Pakistan coach Bob Woolmer in Jamaica on March 18.
South Africa were at the centre of the match-fixing storm in 2000, when former captain Hansie Cronje's involvement was exposed.
Australia beat South Africa by 83 runs in their Group A match in St Kitts on Saturday, and Smith knew the pressure was mounting on his team ahead of their first Super Eights clash with Sri Lanka in Georgetown on Wednesday.
"Sri Lanka are a top team, and I know it sounds like a cliche but we really are taking every game as it comes," Smith said.
SEVERE CRAMP
South Africa's scoring momentum was disrupted on Saturday when Smith had to leave the field with severe cramp after scoring a quickfire 72.
He returned once his condition had improved but by then Australia had established a hold on the match and Smith scored just two more runs before being dismissed.
"It is to be expected that you will become dehydrated in these conditions," Smith said. "It's the first time it's happened to me, I've scored hundreds in these conditions before so it did come as a shock to me.
Smith said the South Africans would be more mindful about the hot and humid Caribbean weather in future.
"Our medical team are working at hydrating the team properly so it doesn't happen to us again," he said.
The last time Sri Lanka and South Africa met on the World Cup stage, in Durban in 2003, a tied match eliminated South Africa from the tournament in the first round.
"We haven't discussed it, but we haven't forgotten about it either," Smith said. "It has not been a major issue in the team since I have taken over the captaincy."
Shaun Pollock was sacked as captain and replaced by Smith in the wake of South Africa's shock early exit.
South Africa were greeted by rain when they arrived in Guyana on Sunday, and similar weather on Monday forced the cancellation of their planned training session.
