I just tried to upgrade to plexus-utils 4 which means adding plexus-xml as dependency here and there, but I had the surprise to notice that both plexus-xml and its direct dependency maven-xml-impl contain 2 classes with the same name and extremely similar code. I was wondering if this is really on purpose since it's not very clean.

I checked Xpp3Dom source and both versions seems very similar, the only changes I noticed are on the final static constants.