No, I hadn't seen that one. But now I have, and I even replied
As was discussed there, I don't think the built-in logging and log4j are interchangable. But the API's are very similar. And here, Will points out a couple of features that the built-in stuff doesn't have (since it violates platform independence, but frankly that's a stupid reason to keep it out in this case IMO).
I'll consider the issue dead. Except for the couple System.out.println's I found in Geom.java that should be replaced with logging statements, if not simply removed altogether. If you're going to do logging, then do logging.