NullPointerException when adding a feature repository to a cluster

I have a cluster with 2 nodes. Both nodes have the feature listener enabled (org.apache.karaf.cellar.node.cfg / feature.listener = true).
On node 1, I install a custom feature repository with following command:

feature:repo-add mvn:com.bechtle.terra/com.bechtle.terra.renderer.feature/LATEST/xml/features

On node 2, I get a NullPointerException:

2016-02-05 11:10:39,849 | ERROR | pool-50-thread-1 | RepositoryEventHandler           | 64 - org.apache.karaf.cellar.features - 4.0.0 | CELLAR FEATURE: failed to add/remove repository URL mvn:com.bechtle.terra/com.bechtle.terra.renderer.feature/LATEST/xml/features
java.lang.NullPointerException
	at org.apache.karaf.cellar.features.RepositoryEventHandler.handle(RepositoryEventHandler.java:80)[64:org.apache.karaf.cellar.features:4.0.0]
	at org.apache.karaf.cellar.features.RepositoryEventHandler.handle(RepositoryEventHandler.java:29)[64:org.apache.karaf.cellar.features:4.0.0]
	at org.apache.karaf.cellar.core.event.EventDispatchTask.run(EventDispatchTask.java:57)[63:org.apache.karaf.cellar.core:4.0.0]
	at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)[:1.7.0_55]
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)[:1.7.0_55]
	at java.lang.Thread.run(Unknown Source)[:1.7.0_55]

The same effect occurs when I use the dedicated cluster command:
cluster:feature-repo-add default mvn:com.bechtle.terra/com.bechtle.terra.renderer.feature/LATEST/xml/features

When I disable the feature listener (org.apache.karaf.cellar.node.cfg / feature.listener = false), the cluster-command
cluster:feature-repo-add default mvn:com.bechtle.terra/com.bechtle.terra.renderer.feature/LATEST/xml/features
works as exepected. The repository is then also available on node 2 and the feature can be installed.

If I did something wrong, it would nevertheless be helpful if an error message would tell what caused the problem.