Test MavenURLResourceTestCase#testMavenGav fails with Connection timed out

The test MavenURLResourceTestCase#testMavenGav fails with "Connection timed out". This makes the default build fail for me, so I added an Ignored to the test case and till now no other test failed.

I have no direct Internet connection, but I am behind a http proxy and building JBoss worked before. I am on Ubuntu 11.04 and the proxy settings are added to ~/.m2/settings.xml and some environment variables with the proxy url are also set.
This class with the failing test was added in 1a7d15d924f7df70115b22a067ead3882c61a184 by kabir <kkhan@redhat.com>. I am using the 7.1 branch from github.

The error message:

testMavenGav(org.jboss.as.subsystem.test.MavenURLResourceTestCase) Time elapsed: 190.173 sec <<< ERROR!
java.lang.RuntimeException: org.sonatype.aether.resolution.ArtifactResolutionException: Could not transfer artifact org.sonatype.aether:aether-api:jar:1.13.1 from/to jboss-developer (http://repository.jboss.org/nexus/content/groups/developer/): Error transferring file: Connection timed out