BPMS 6.0.x server fails to start properly after receiving this error on business-central.war deployment "JBAS011046: A component called 'MailboxProcessOutgoingExecutorManager' is already defined in this module"

Issue

• While upgrading to BPMS from 6.0.2 to 6.0.3 as per the documentation [1] fails to start the server properly after receiving this error on business-central.war deployment as shown below. What could be the root cause of this issue?

[31m15:46:30,804 ERROR [org.jboss.msc.service.fail] (MSC service thread 1-16) MSC000001: Failed to start service jboss.deployment.unit."dashbuilder.war".PARSE: org.jboss.msc.service.StartException in service jboss.deployment.unit."dashbuilder.war".PARSE: JBAS018733: Verarbeitung von Phase PARSE von deployment "dashbuilder.war" fehlgeschlagen
    at org.jboss.as.server.deployment.DeploymentUnitPhaseService.start(DeploymentUnitPhaseService.java:127) [jboss-as-server-7.2.1.Final-redhat-10.jar:7.2.1.Final-redhat-10]
    at org.jboss.msc.service.ServiceControllerImpl$StartTask.startService(ServiceControllerImpl.java:1811) [jboss-msc-1.0.4.GA-redhat-1.jar:1.0.4.GA-redhat-1]
    at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1746) [jboss-msc-1.0.4.GA-redhat-1.jar:1.0.4.GA-redhat-1]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) [rt.jar:1.7.0_51]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) [rt.jar:1.7.0_51]
    at java.lang.Thread.run(Thread.java:744) [rt.jar:1.7.0_51]
Caused by: org.jboss.as.server.deployment.DeploymentUnitProcessingException: JBAS018031: Konflikt bei der Bearbeitung des Web-Fragments in JAR: dashboard-ui-core-6.0.3-redhat-6.jar
    at org.jboss.as.web.deployment.WarMetaDataProcessor.deploy(WarMetaDataProcessor.java:292)
    at org.jboss.as.server.deployment.DeploymentUnitPhaseService.start(DeploymentUnitPhaseService.java:120) [jboss-as-server-7.2.1.Final-redhat-10.jar:7.2.1.Final-redhat-10]
    ... 5 more
Caused by: java.lang.IllegalStateException: Unresolved conflict on load on startup
    at org.jboss.metadata.merge.web.spec.ServletMetaDataMerger.augment(ServletMetaDataMerger.java:152)
    at org.jboss.metadata.merge.web.spec.ServletsMetaDataMerger.augment(ServletsMetaDataMerger.java:35)
    at org.jboss.metadata.merge.web.spec.WebCommonMetaDataMerger.augment(WebCommonMetaDataMerger.java:313)
    at org.jboss.as.web.deployment.WarMetaDataProcessor.deploy(WarMetaDataProcessor.java:290)
    ... 6 more
...
[31m15:46:32,814 ERROR [org.jboss.msc.service.fail] (MSC service thread 1-7) MSC000001: Failed to start service jboss.deployment.unit."business-central.war".PARSE: org.jboss.msc.service.StartException in service jboss.deployment.unit."business-central.war".PARSE: JBAS018733: Verarbeitung von Phase PARSE von deployment "business-central.war" fehlgeschlagen
    at org.jboss.as.server.deployment.DeploymentUnitPhaseService.start(DeploymentUnitPhaseService.java:127) [jboss-as-server-7.2.1.Final-redhat-10.jar:7.2.1.Final-redhat-10]
    at org.jboss.msc.service.ServiceControllerImpl$StartTask.startService(ServiceControllerImpl.java:1811) [jboss-msc-1.0.4.GA-redhat-1.jar:1.0.4.GA-redhat-1]
    at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1746) [jboss-msc-1.0.4.GA-redhat-1.jar:1.0.4.GA-redhat-1]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) [rt.jar:1.7.0_51]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) [rt.jar:1.7.0_51]
    at java.lang.Thread.run(Thread.java:744) [rt.jar:1.7.0_51]
Caused by: java.lang.IllegalArgumentException: JBAS011046: Eine Komponente namens 'MailboxProcessOutgoingExecutorManager' ist bereits in diesem Modul definiert
    at org.jboss.as.ee.component.EEModuleDescription.addComponent(EEModuleDescription.java:140)
    at org.jboss.as.ejb3.deployment.processors.EJBComponentDescriptionFactory.addComponent(EJBComponentDescriptionFactory.java:60)
    at org.jboss.as.ejb3.deployment.processors.SessionBeanComponentDescriptionFactory.processSessionBeans(SessionBeanComponentDescriptionFactory.java:155)
    at org.jboss.as.ejb3.deployment.processors.SessionBeanComponentDescriptionFactory.processAnnotations(SessionBeanComponentDescriptionFactory.java:96)
    at org.jboss.as.ejb3.deployment.processors.AnnotatedEJBComponentDescriptionDeploymentUnitProcessor.processAnnotations(AnnotatedEJBComponentDescriptionDeploymentUnitProcessor.java:58)
    at org.jboss.as.ejb3.deployment.processors.AbstractDeploymentUnitProcessor.deploy(AbstractDeploymentUnitProcessor.java:81)
    at org.jboss.as.server.deployment.DeploymentUnitPhaseService.start(DeploymentUnitPhaseService.java:120) [jboss-as-server-7.2.1.Final-redhat-10.jar:7.2.1.Final-redhat-10]
    ... 5 more

The errors are translated in English as.

JBAS018031: Conflict in processing the web fragment in JAR: dashboard-ui-core-6.0.3-redhat-6.jar
...
JBAS011046: A component called 'MailboxProcessOutgoingExecutorManager' is already defined in this module

[1] 2.2.2. Installing the EAP6 package