Artifact copier does not handle '301 Moved Permanently'

When jira2.bamboo.atlassian.com was renamed jira.bamboo.atlassian.com the artifact copier stopped working (though the builds still passed):

Failed to execute plugin 'Artifact Copier' with error: java.io.IOException: Unexpected HTTP status code: 301 Moved Permanently

What happened is that jira2.bamboo.atlassian.com is now redirecting to jira.bamboo.atlassian.com and the agents are still (mis-)configured to communicate to https://jira2.bamboo.atlassian.com/agentServer/. The agents seem to handle the redirect correctly, but the artifact copier does not.