I appreciate all the comments. Just a little more background. The print engine is currently crashing and randomly not printing things properly. A couple co-workers, not the person that supports it, spent three months trying to fix the memory leaks and set the print engine right. After three months things were better, but some things could not be completely fixed including it randomly crashing and on occasion it would be missing a print page in the middle of the print job. During these three months, the co-work that supports the print engine made no move to try and fix things, which is why these other co-workers had to get involved in the first place. The interesting thing is after I wrote this article and tasks were assigned to the co-work that currently support the print engine to get them involved, they didn't do the tasks they were asked to do. It is a bit maddening as they wanted to be involved, but once they were involved they didn't do what they were supposed to do. So again, another co-worker has to do what was assigned to them to meet project deadlines. There is more to say, but I think I have disparaged my co-work enough.
Ben
From this, I would suggest the co-worker doesn't agree that the project is required or heading in the right direction. I would get them in on meetings etc to work out what they think is flawed, what they think needs changing and come to a compromise. Yes, it may be that they are fed up with what they do or may be protectionist about their role, but its up to the manager/project leader to deal with that and try to get the person on board with the changes, rather than dictating terms to your co-worker. Remember, if they are the one supporting the current system, they probably know the flaws and the good bits inside out and therefore are a valuable resource.