KARACHI  - Pakistan's plans for a domestic Twenty20 competition along the lines of the Indian Premier League hit a snag Tuesday as South Africa refused to reschedule their series to accommodate the tournament.After the huge success of the IPL and similar leagues around the world, the Pakistan Cricket Board (PCB) is planning to launch their own version, partly as an effort to lure overseas cricketers back to the troubled country. International cricket has been suspended in Pakistan over security worries since deadly militant attacks on the Sri Lankan team bus during the second Test in Lahore in March 2009.The PCB wanted to stage the Pakistan Premier League (PPL) in March next year but the plan was set back after South Africa refused to rearrange the Pakistan national team's tour. Pakistan are scheduled to play three Tests, five one-day internationals and two T20s between February 1 and March 24 and wanted the tour to be pushed forward to accommodate the PPL."We requested Cricket South Africa to change the itinerary so that we could expand the window for our Premier league, but they said that the tickets for the series are already sold out and it's not possible now," PCB spokesman Nadeem Sarwar told AFP. "We understand their position and are comfortable with that," said the spokesman.The dates of the South African tour leave only a tiny window before the lucrative IPL, which attracts most of the game's biggest stars, begins on April 3. Reports in local media claim the PCB has offered substantial sums of money to players from Sri Lanka, Bangladesh, Australia and the West Indies to appear in the PPL, but security fears will be a huge hurdle to convincing them to come.Pakistan successfully hosted two Twenty20 exhibition matches with an International World XI involving players from Sri Lanka, South Africa, the West Indies and Afghanistan in Karachi on Saturday and Sunday.