Error closing plugin test

I'm developing a plugin that depends on the Maven plugin and when I run the plugin to test it during development I get the error below when I close the instance of Intellij that is spawned when I run the plugin from the 'Run Plugin' run configuration button.

Can anyone help to resolve this?

Thanks, Andy.

[INFO] Maven execution finished[ 610718]   WARN - pl.local.NativeFileWatcherImpl - Watcher terminated with exit code 0
[ 610919]  ERROR - j.openapi.util.ShutDownTracker - null
java.util.concurrent.RejectedExecutionException
 at java.util.concurrent.ThreadPoolExecutor$AbortPolicy.rejectedExecution(ThreadPoolExecutor.java:1774)
 at java.util.concurrent.ThreadPoolExecutor.reject(ThreadPoolExecutor.java:768)
 at java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:656)
 at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:78)
 at com.intellij.openapi.application.impl.ApplicationImpl.executeOnPooledThread(ApplicationImpl.java:360)
 at com.intellij.execution.rmi.RemoteProcessSupport.stopAll(RemoteProcessSupport.java:92)
 at org.jetbrains.idea.maven.server.MavenServerManager.shutdown(MavenServerManager.java:181)
 at org.jetbrains.idea.maven.server.MavenServerManager$2.run(MavenServerManager.java:152)
 at com.intellij.openapi.util.ShutDownTracker.run(ShutDownTracker.java:60)
 at java.lang.Thread.run(Thread.java:662)
[ 610922]  ERROR - j.openapi.util.ShutDownTracker - IntelliJ IDEA 15.0.1  Build #IC-143.382.35
[ 610923]  ERROR - j.openapi.util.ShutDownTracker - JDK: 1.6.0_41
[ 610923]  ERROR - j.openapi.util.ShutDownTracker - VM: Java HotSpot(TM) Client VM
[ 610923]  ERROR - j.openapi.util.ShutDownTracker - Vendor: Sun Microsystems Inc.
[ 610923]  ERROR - j.openapi.util.ShutDownTracker - OS: Windows 7