Can an Outback run on biodiesel?

[cunnerz]

I love my 2002 Outback but it drinks too much petrol around town. I was thinking of buying a new boxer diesel engine (or obtaining one from a wreckers if one were available) and swapping it for my 2.5 litre petrol engine. Does anyone know if the boxer engine will run on biodiesel made from cooking oil? I've found a supplier of biodiesel in my area that sells it for $1 per litre and it appears a good way to save money and the environment. Thanks.