sbcmac4 - 2006-06-21

I am going through the project function and have hit a stump.  I have setup a project(service) inside Compiere with phases and tasks.  I basically want the project function to work as a worktracker to take me through a manufacturing process, but then for it to invoice the project(service).  I do not have any product assigned to the project.  I get an error that reads "Error starting Class org.compiere.process.ProjectPhaseGenOrder"  Will I be able to use the project function the way I explained, or how is this primarily used?