Cook the pasta in boiling salted water until al dente, drain.
Rinse the lentils in cold water in a sieve, then drain. Heat the oil in a pan, sauté the onion, add the lentils and cook briefly. Add the carrot, pour in the wine, bring to the boil and reduce a little. Pour in the tomatoes and water, bring to the boil, simmer over a low heat for approx. 20 mins. Season the sauce, mix in the penne, heat through and serve immediately.