Errors in log file after upgrading Jira Gantt-Chart plugin to v.3.1.0.-JIRA6

[Vidic Florjan]

Our log file is full of error messages after upgrading Jira Gantt-Chart plugin to v.3.1.0.-JIRA6 (from 3.0.0). Errors are logged after creating or updating issues. Problem still persist if we disable Gantt-Charts on all projects.
Does anyone have the same problem? Is this an known error?

Thanks,
Florjan

Version: 3.1.0-JIRA6

Jira version: 6.1.3
Example of error in log file:

2014-02-24 09:40:59,628 ajp-bio-8009-exec-187 ERROR VidicF 580x64268x1 ssmtyd 193.77.55.10 /secure/CreateIssueDetails.jspa [atlassian.event.internal.AsynchronousAbleEventDispatcher] There was an exception thrown trying to dispatch event 'com.atlassian.jira.event.issue.IssueEvent@728b6204[issue=JRAS-216,comment=<null>,worklog=<null>,changelog=<null>,eventTypeId=1,sendMail=true,params={eventsource=workflow, baseurl=https://jira.telxxxxxx.xx},subtasksUpdated=false]' from the invoker 'SingleParameterMethodListenerInvoker{method=public void de.polscheit.jira.listener.GanttListener.onIssueEvent(com.atlassian.jira.event.issue.IssueEvent), listener=de.polscheit.jira.listener.GanttListener@10b93740}'.
java.lang.RuntimeException: java.lang.NullPointerException
at com.atlassian.event.internal.SingleParameterMethodListenerInvoker.invoke(SingleParameterMethodListenerInvoker.java:50)
at com.atlassian.event.internal.AsynchronousAbleEventDispatcher$2.run(AsynchronousAbleEventDispatcher.java:66)
at com.atlassian.event.internal.AsynchronousAbleEventDispatcher$1.execute(AsynchronousAbleEventDispatcher.java:32)
at com.atlassian.event.internal.AsynchronousAbleEventDispatcher.dispatch(AsynchronousAbleEventDispatcher.java:60)
at com.atlassian.event.internal.EventPublisherImpl.invokeListeners(EventPublisherImpl.java:160)
at com.atlassian.event.internal.EventPublisherImpl.publish(EventPublisherImpl.java:79)
at com.atlassian.jira.event.issue.IssueEventDispatcher.dispatchEvent(IssueEventDispatcher.java:184)
at com.atlassian.jira.event.issue.IssueEventDispatcher.dispatchEvent(IssueEventDispatcher.java:134)
at com.atlassian.jira.workflow.function.event.FireIssueEventFunction.execute(FireIssueEventFunction.java:60)
at com.opensymphony.workflow.AbstractWorkflow.executeFunction(AbstractWorkflow.java:1050)

[Frank Polscheit · Accepted solution]

Fixed within Gantt-Chart v3.1.1 as validated by Florjan Vidic within a separate email thread.