When a "comment added" event is detected it crashes with a NullException, see below.

I also saw the following warning message:
WARNING: No GerritHandler was specified, won't register as event listener, so no function.

It looks like the whole thing is caused when a Null GerritHandler gets passed here.
https://github.com/jenkinsci/gerrit-trigger-plugin/blob/master/src/main/java/com/sonyericsson/hudson/plugins/gerrit/trigger/replication/ReplicationQueueTaskDispatcher.java#L107

Here is logg when it crashes on a comment added event:

INFO: Project [xxxx] triggered by Gerrit: [com.sonymobile.tools.gerrit.gerritevents.dto.events.CommentAdded@58561316]
Oct 13, 2016 10:36:47 PM com.sonymobile.tools.gerrit.gerritevents.GerritHandler notifyListener
SEVERE: Exception thrown during event handling.
java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at com.sonymobile.tools.gerrit.gerritevents.GerritHandler.notifyListener(GerritHandler.java:316)
at com.sonymobile.tools.gerrit.gerritevents.GerritHandler.notifyListeners(GerritHandler.java:296)
at com.sonyericsson.hudson.plugins.gerrit.trigger.JenkinsAwareGerritHandler.notifyListeners(JenkinsAwareGerritHandler.java:77)
at com.sonymobile.tools.gerrit.gerritevents.workers.AbstractGerritEventWork.perform(AbstractGerritEventWork.java:46)
at com.sonymobile.tools.gerrit.gerritevents.workers.AbstractJsonObjectWork.perform(AbstractJsonObjectWork.java:77)
at com.sonymobile.tools.gerrit.gerritevents.workers.StreamEventsStringWork.perform(StreamEventsStringWork.java:67)
at com.sonymobile.tools.gerrit.gerritevents.workers.EventThread.run(EventThread.java:66)
at com.sonyericsson.hudson.plugins.gerrit.trigger.SystemEventThread.run(SystemEventThread.java:66)
Caused by: java.lang.NullPointerException
at com.sonyericsson.hudson.plugins.gerrit.trigger.hudsontrigger.GerritTriggerParameters.setOrCreateParameters(GerritTriggerParameters.java:447)
at com.sonyericsson.hudson.plugins.gerrit.trigger.hudsontrigger.EventListener.createParameters(EventListener.java:263)
at com.sonyericsson.hudson.plugins.gerrit.trigger.hudsontrigger.EventListener.schedule(EventListener.java:188)
at com.sonyericsson.hudson.plugins.gerrit.trigger.hudsontrigger.EventListener.schedule(EventListener.java:164)
at com.sonyericsson.hudson.plugins.gerrit.trigger.hudsontrigger.EventListener.gerritEvent(EventListener.java:152)
... 12 more

Please let me know if you need anything else from my side.
Best regards