From IRC:

[2:13pm] ianbrandt: aslak, Should @ArquillianResource injection work for in-container test cases? It works fine when I try it for an as-client test, but when I do the same in-container the org.jboss.arquillian.container.test.impl.enricher.resource.URLResourceProvider.protocolMetadata.get() is null, so no context URL. I verified the container is returning a non-null ProtocolMetaData from deploy(...).
[2:15pm] aslak: ianbrandt, no it currently doesn't work
[2:16pm] aslak: ianbrandt, it probably should, but i'm not sure we have the info incontianer without doing a callback to the client..
[2:16pm] aslak: ianbrandt, but then we don't know which deployment we are when incontianer, so we have a little problem there..
[2:17pm] ianbrandt: aslak, Ah, okay.
[2:17pm] aslak: no wait we do
[2:18pm] aslak: the Protocol is executed within a DeploymentScope/ContainerScope, so when it gets the callback, it has the correct context..
[2:18pm] aslak: we tho need OperatesOnDeployment support for that tho, cuz you possible want to inject URLs not to your self, but to another deployment on possible another contianer that you should invoke from incontainer
[2:19pm] aslak: so from incontianer on dep 1, we can do @ArqRes @OperatesOnDep("dep2") URL url;
[2:23pm] ianbrandt: aslak, Makes sense. It's a little more than I could take on at the moment. I was just augmenting the Tomcat tests to show @ArqRes usage. I'll skip it for shouldBeAbleToInvokeServletInDeployedWebApp, and JIRA+Wiki the limitation.