Or I should ask how does any tool besides Adobe LiveCycle designer handles XFA. I've been using Apache Tika with Apache Solr to index PDF documents -- it worked quite well up until I tried to index XFA-based documents and got nothing, well I got metdatada, but not the content.
A Kivy [1] based cross-platform GUI would be a nice addition at some point.
[1] http://kivy.org