Jetty is a GREAT servlet engine, which I mainly used for development. Yet, you can use it for production as well.
Developing with Jetty is very easy already, but if you need to get going NOW, this may help:
RunJettyRun
If you work with Eclipse, and want an integrated Jetty for development, all you need id this:
http://code.google.com/p/run-jetty-run/wiki/GettingStarted
Change Port when using maven
Jetty runs on port 8080 by default. How you change that port in RunJettyRun is pretty easy (just change the run config).
If you start Jetty using Maven on the command line with this command:
mvn jetty:run
you can change the port by specifying the runtime variable jetty.port. For example, if you want to use port 8900 instead, use the following command:
mvn -Djetty.port=8900 jetty:run
I know this is not rocket science, but this kind of information may help you to get going with Jetty even faster.