Validating a process in jBPM Web Designer containing a Service Task inside Swim Lane complains "java.lang.IllegalArgumentException: No interfaces found"

Issue

• Validating a process (containing a Service Task inside Swim Lane) in jBPM Web Designer complains with ERROR java.lang.IllegalArgumentException: No interfaces found , as quoted below. It seems that this issue specifically happens when using Service Tasks inside Swim Lane. Is it a known issue?

14:20:53,669 ERROR [stderr] (pool-119-thread-2) java.lang.IllegalArgumentException: No interfaces found
14:20:53,669 ERROR [stderr] (pool-119-thread-2)         at org.jbpm.bpmn2.xml.ServiceTaskHandler.handleNode(ServiceTaskHandler.java:52)
14:20:53,669 ERROR [stderr] (pool-119-thread-2)         at org.jbpm.bpmn2.xml.TaskHandler.end(TaskHandler.java:168)
14:20:53,669 ERROR [stderr] (pool-119-thread-2)         at org.drools.core.xml.ExtensibleXmlParser.endElement(ExtensibleXmlParser.java:422)
14:20:53,669 ERROR [stderr] (pool-119-thread-2)         at org.apache.xerces.parsers.AbstractSAXParser.endElement(Unknown Source)
14:20:53,670 ERROR [stderr] (pool-119-thread-2)         at org.apache.xerces.impl.xs.XMLSchemaValidator.endElement(Unknown Source)
14:20:53,670 ERROR [stderr] (pool-119-thread-2)         at org.apache.xerces.impl.XMLNSDocumentScannerImpl.scanEndElement(Unknown Source)
14:20:53,670 ERROR [stderr] (pool-119-thread-2)         at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl$FragmentContentDispatcher.dispatch(Unknown Source)
14:20:53,670 ERROR [stderr] (pool-119-thread-2)         at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
14:20:53,670 ERROR [stderr] (pool-119-thread-2)         at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)
14:20:53,670 ERROR [stderr] (pool-119-thread-2)         at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)
14:20:53,671 ERROR [stderr] (pool-119-thread-2)         at org.apache.xerces.parsers.XMLParser.parse(Unknown Source)
14:20:53,671 ERROR [stderr] (pool-119-thread-2)         at org.apache.xerces.parsers.AbstractSAXParser.parse(Unknown Source)
14:20:53,671 ERROR [stderr] (pool-119-thread-2)         at org.apache.xerces.jaxp.SAXParserImpl$JAXPSAXParser.parse(Unknown Source)
14:20:53,671 ERROR [stderr] (pool-119-thread-2)         at org.apache.xerces.jaxp.SAXParserImpl.parse(Unknown Source)
14:20:53,671 ERROR [stderr] (pool-119-thread-2)         at org.drools.core.xml.ExtensibleXmlParser.read(ExtensibleXmlParser.java:301)
14:20:53,671 ERROR [stderr] (pool-119-thread-2)         at org.drools.core.xml.ExtensibleXmlParser.read(ExtensibleXmlParser.java:180)
14:20:53,671 ERROR [stderr] (pool-119-thread-2)         at org.jbpm.compiler.xml.XmlProcessReader.read(XmlProcessReader.java:46)
14:20:53,671 ERROR [stderr] (pool-119-thread-2)         at org.jbpm.compiler.ProcessBuilderImpl.addProcessFromXml(ProcessBuilderImpl.java:276)
14:20:53,672 ERROR [stderr] (pool-119-thread-2)         at org.drools.compiler.compiler.PackageBuilder.addProcessFromXml(PackageBuilder.java:699)
14:20:53,672 ERROR [stderr] (pool-119-thread-2)         at org.drools.compiler.compiler.CompositeKnowledgeBuilderImpl.buildResources(CompositeKnowledgeBuilderImpl.java:149)
14:20:53,672 ERROR [stderr] (pool-119-thread-2)         at org.drools.compiler.compiler.CompositeKnowledgeBuilderImpl.build(CompositeKnowledgeBuilderImpl.java:86)
14:20:53,672 ERROR [stderr] (pool-119-thread-2)         at org.drools.compiler.kie.builder.impl.KieBuilderSetImpl.buildChanges(KieBuilderSetImpl.java:121)
14:20:53,672 ERROR [stderr] (pool-119-thread-2)         at org.drools.compiler.kie.builder.impl.KieBuilderSetImpl.build(KieBuilderSetImpl.java:76)
14:20:53,672 ERROR [stderr] (pool-119-thread-2)         at org.guvnor.common.services.builder.Builder.addResource(Builder.java:290)
14:20:53,672 ERROR [stderr] (pool-119-thread-2)         at org.guvnor.common.services.builder.Builder.updateResource(Builder.java:394)
14:20:53,673 ERROR [stderr] (pool-119-thread-2)         at org.guvnor.common.services.builder.BuildServiceImpl.updatePackageResource(BuildServiceImpl.java:216)
14:20:53,673 ERROR [stderr] (pool-119-thread-2)         at org.guvnor.common.services.builder.BuildServiceImpl$Proxy$_$$_WeldClientProxy.updatePackageResource(BuildServiceImpl$Proxy$_$$_WeldClientProxy.java)
14:20:53,673 ERROR [stderr] (pool-119-thread-2)         at org.guvnor.common.services.builder.ResourceChangeIncrementalBuilder$4.run(ResourceChangeIncrementalBuilder.java:243)
14:20:53,673 ERROR [stderr] (pool-119-thread-2)         at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
14:20:53,673 ERROR [stderr] (pool-119-thread-2)         at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
14:20:53,673 ERROR [stderr] (pool-119-thread-2)         at java.lang.Thread.run(Thread.java:662)
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