I’ve been using newgem to build Babelphish (translation helper thing). The docs from the ruby forge site are a bit out of date. If you use newgem to build anything be sure to look at this post from Dr Nic and pay attention to the options you can pass in. In particular I noticed that the instructions on the rubyforge site indicate the gem will build a default website. If you want to do that you need to pass in the -w option.