After upgradeing from 2.10.0 to 2.10.1 at startup jenkins emits the following warning

Jun 18, 2013 5:07:32 PM com.sonyericsson.hudson.plugins.gerrit.trigger.version.GerritVersionChecker createVersionNumber
SEVERE: Gerrit version number is null or the empty string.
Jun 18, 2013 5:07:32 PM com.sonyericsson.hudson.plugins.gerrit.gerritevents.GerritHandler run
INFO: Ready to receive data from Gerrit

This is obviously not good (our Gerrit version is 2.5) and has been detected correctly before. So the plugin may now expect functionality from Gerrit that our server does not support.