Not exactly, the DPF is only for particulates. They couldn't use them until the government required ultra low sulfur diesel because otherwise it would clog the filter.
Urea is for NOx. NOx is made under high temps with free oxygen. Diesels run lean. EGR helps lower NOx. The Jetta is light enough to not require it. The Passat and larger cars/engines use urea with a special catalyst to break down nox.
IMHO, the best solution is to have an extra injector for post injection combustion- no worries about fuel in the crankcase or biodiesel. However, this adds cost. Urea is nice because it greatly simplifies the exhaust system and isn't too expensive.