whunter,

Biodiesel will likely eat up the old fuel lines. You will probably want to replace them if you plan on running 100% biodiesel, but you can always wait and see if they start leaking before replacing them.

Otherwise, everything else should be fine. Biodiesel is really cool. I ran a tank of B100 in my New Beetle a few years ago, and the engine really quieted down. Power and fuel economy dropped about 10%, which isn't a huge deal.

http://www.biodieselnow.org