We had identical problem with version 1.419. Also started around sep 8. Upgrading to latest Jenkins solved the problem.
-- View this message in context: http://jenkins.361315.n4.nabble.com/JIRA-JENKINS-15105-Signature-in-hudson-tasks-Maven-MavenInstaller-json-causes-NullPointerException-tp4639778p4639859.html Sent from the Jenkins issues mailing list archive at Nabble.com.