Doug,
I bet this might be a linking problem when you map the pipeline record to the input of javaservice reason might be the syncpurchaseorder record in the pipeline and the input signature of your javaservice not matching.So please debug and step thru the flow starting from the restorepipeline to before invoking the javaservice and check the pipeline if something is missing or anything new is getting passed etc… in the output record ie documentToRecord step.Also make sure whether node exits in the pipeline ofcourse you crossed this point.
If you are sure everything is fine then we have work out differently what the root cause is.
HTH,
RMG…