In a pan, mix the tomatoes with all the other ingredients up to and including the sugar, bring to the boil. Reduce the heat, cover and simmer over a low heat for approx. 20 mins., stirring occasionally, then puree.
Divide the sauce in half, mix the sambal oelek into one half to create two sauces.
Charcoal/gas/electric grill: Grill the sausages over/on a medium heat (approx. 180 °C for approx. 10 mins. all over. Cut the sausages into slices, serve with the sauces, sprinkle with curry powder.