I am reading in existing feeds and the tags above are not supported in the output. I think <managingEditor> and <webMaster> may get converted to DC equivalents.
I'm just curious as to why these tags are not supported. Maybe they should be. They are in this: http://www.rssboard.org/rss-profile
Java 1.6, Mac OSX but I don't think this is relevant.
This is a fix I made so that <comments> tag is generated in RSS 2.0