Spark streaming processor module: Dispatcher has no subscribers

The spark streaming processor module emits the following exception when there are more messages in the RDD partitions:

015-02-17 12:45:02,026 1.2.0.SNAP ERROR Executor task launch worker-2 executor.Executor - Exception in task 0.0 in stage 56.0 (TID 142)
org.springframework.messaging.MessageDeliveryException: Dispatcher has no subscribers for channel 'output'.; nested exception is org.springframework.integration.MessageDispatchingException: Dispatcher has no subscribers
at org.springframework.integration.channel.AbstractSubscribableChannel.doSend(AbstractSubscribableChannel.java:81)
at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:277)
at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:239)
at org.springframework.xd.dirt.plugins.spark.streaming.MessageBusSender.send(MessageBusSender.java:105)
at org.springframework.xd.spark.streaming.java.ModuleExecutor$1$1.call(ModuleExecutor.java:80)
at org.springframework.xd.spark.streaming.java.ModuleExecutor$1$1.call(ModuleExecutor.java:55)
at org.apache.spark.api.java.JavaRDDLike$$anonfun$foreachPartition$1.apply(JavaRDDLike.scala:195)
at org.apache.spark.api.java.JavaRDDLike$$anonfun$foreachPartition$1.apply(JavaRDDLike.scala:195)
at org.apache.spark.rdd.RDD$$anonfun$foreachPartition$1.apply(RDD.scala:790)
at org.apache.spark.rdd.RDD$$anonfun$foreachPartition$1.apply(RDD.scala:790)
at org.apache.spark.SparkContext$$anonfun$runJob$4.apply(SparkContext.scala:1353)
at org.apache.spark.SparkContext$$anonfun$runJob$4.apply(SparkContext.scala:1353)
at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:61)
at org.apache.spark.scheduler.Task.run(Task.scala:56)
at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:200)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Caused by: org.springframework.integration.MessageDispatchingException: Dispatcher has no subscribers
at org.springframework.integration.dispatcher.UnicastingDispatcher.doDispatch(UnicastingDispatcher.java:107)
at org.springframework.integration.dispatcher.UnicastingDispatcher.dispatch(UnicastingDispatcher.java:97)
at org.springframework.integration.channel.AbstractSubscribableChannel.doSend(AbstractSubscribableChannel.java:77)
... 17 more
2015-02-17 12:45:02,032 1.2.0.SNAP WARN task-result-getter-1 scheduler.TaskSetManager - Lost task 0.0 in stage 56.0 (TID 142, localhost): org.springframework.messaging.MessageDeliveryException: Dispatcher has no subscribers for channel 'output'.; nested exception is org.springframework.integration.MessageDispatchingException: Dispatcher has no subscribers
at org.springframework.integration.channel.AbstractSubscribableChannel.doSend(AbstractSubscribableChannel.java:81)
at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:277)
at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:239)
at org.springframework.xd.dirt.plugins.spark.streaming.MessageBusSender.send(MessageBusSender.java:105)
at org.springframework.xd.spark.streaming.java.ModuleExecutor$1$1.call(ModuleExecutor.java:80)
at org.springframework.xd.spark.streaming.java.ModuleExecutor$1$1.call(ModuleExecutor.java:55)
at org.apache.spark.api.java.JavaRDDLike$$anonfun$foreachPartition$1.apply(JavaRDDLike.scala:195)
at org.apache.spark.api.java.JavaRDDLike$$anonfun$foreachPartition$1.apply(JavaRDDLike.scala:195)
at org.apache.spark.rdd.RDD$$anonfun$foreachPartition$1.apply(RDD.scala:790)
at org.apache.spark.rdd.RDD$$anonfun$foreachPartition$1.apply(RDD.scala:790)
at org.apache.spark.SparkContext$$anonfun$runJob$4.apply(SparkContext.scala:1353)
at org.apache.spark.SparkContext$$anonfun$runJob$4.apply(SparkContext.scala:1353)
at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:61)
at org.apache.spark.scheduler.Task.run(Task.scala:56)
at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:200)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Caused by: org.springframework.integration.MessageDispatchingException: Dispatcher has no subscribers
at org.springframework.integration.dispatcher.UnicastingDispatcher.doDispatch(UnicastingDispatcher.java:107)
at org.springframework.integration.dispatcher.UnicastingDispatcher.dispatch(UnicastingDispatcher.java:97)
at org.springframework.integration.channel.AbstractSubscribableChannel.doSend(AbstractSubscribableChannel.java:77)
... 17 more