Our team uses the wagon-maven-plugin to deliver some artifacts to a distant server, via scp. Everyone has their SSH public key stored on the distant computer, so no login/password is necessary.
Some members of the team are using Ubuntu 10.04 and everything is OK. However, two members have switched to Ubuntu 11.04 and the wagon plugin just hangs upon execution. Launching the wagon plugin separately (outside of the release lifecycle) reveals that it's actually waiting for the user to enter the password. I should mention that these users can login without password on the distant server via ssh.
The Maven wagon plugin uses JSch to provide scp transport, and JSch files are embedded in Maven's uber-jar. Upon inspection, it turns out Maven is using version 0.1.42 of JSch, which, on Ubuntu 11.04, fails to authenticate using public/private keys on the distant server.
As a workaround, I replaced the JSch files in Maven's uber-jar with those from version 0.1.44 and they can now upload via SCP on Ubuntu 11.04. This being an ugly solution, I think Maven 2.2.2 should upgrade to using JSch 0.1.44.
I can, of course, provide more detail, if needed.