Testing servlet redirects

Hello,

i am using the JettyTestSetup to test a simple Servlet. This servlet
sometimes calls
getServletContext().getNamedDispatcher("default").forward(request,
response); to redirect requests to the default servlet to serve static
resources.

Well this is what Jetty returns as response when such a redirect happens:
HTTP ERROR: 404 /core/ServletRedirector Not Found
RequestURI=/core/ServletRedirector
Where core is the context path.

It is not important for me to test what the redirect returns, its more
important that the servlet performs the redirect. That is what I want to
test.
Any ideas on how to test that (Testing for this error message would be a
very hacky solution)?

greetings
Dennis :)