Smith was found guilty of breaching the ICC code of conduct by Match Referee Chris Broad in a hearing after play concluded in Cape Town yesterday, an ICC release said here today.
The hearing was attended by the on-field umpires, Smith, South African coach Micky Arthur and manager Goolam Raja.
The South African skipper was found to have breached Level 1.3 of the code which relates to ''Showing serious dissent at an umpire's decision by action or verbal abuse'' after being given out lbw in the second innings.
''As captain of his side Graeme needs to lead by example,'' Broad said.
''His actions on his dismissal were not acceptable. He is aware of this and has apologised for his actions. I hope that we will not see this sort of behaviour from him again,'' he added.