Stir together the vinegar, light soy, sesame oil and oil. Wrap the tofu in paper towel and leave for 25-30 minutes, changing the paper towel at times when soaked, to remove excess water. Cut the tofu into bite size cubes and put in a bowl along with the tomatoes. Pour the vinegar mixture over and carefully toss (trying not to break the tofu). Sprinkle the mint over, season with salt and pepper, and serve.