I just went on a little hunting spree with my mum and the two other kids.
According to the cab driver in Malaysia, there is a Pasar Malam just outside of KSL city, JB, on Monday evenings (every Monday). The roads will be blocked by the police then, so it is a little like the Pasar Malam in Jonker Street.
However, the stuff that they sell there is a little different from Jonker Street. They sell food and vegetables more than they sell little trinkets and clothes. There are only a few clothes shops here and there but there are lots of food stalls. It is a must-go place if you are interested in local food. There are bread, cakes, mua chi, corn, etc sold there piping hot.
Just look out for the entrance/exit near to coffeebean in KSL City ;)