I use Jetty 9 and have some problems with configuration. I simple RESTs works fine. But the problem begun when I tried to add new headers to all requests and error handler.
Similar approach as peeskillet mentioned, but I have held jetty configuration in jetty.xml in my application.
So to add custom filters I had to register them in the jetty.xml file as:
com.sun.jersey.config.property.packages ...my package com.sun.jersey.spi.container.ContainerResponseFilters ...MyCorsResponseFilter