When I start the jbpm console for my bpmn flows I get below mentioned errors. if i drop all the tables and create new schema and start the jbpm console , I dont get below errors for my workflows.

Looks like that in serialization and saving the process data some issue happens

— Error ----

11:56:17,514 WARN [org.jbpm.ruleflow.core.validation.RuleFlowProcessValidator] (pool-22-thread-1) Process variable pvObjArray uses ObjectDataType for default type (java.lang) which could cause problems with setting variables, use dedicated type instead
11:56:17,533 WARN [org.jbpm.ruleflow.core.validation.RuleFlowProcessValidator] (pool-22-thread-1) Process variable pvException uses ObjectDataType for default type (java.lang) which could cause problems with setting variables, use dedicated type instead
11:56:17,932 WARN [org.jbpm.ruleflow.core.validation.RuleFlowProcessValidator] (pool-22-thread-1) Process variable pvException uses ObjectDataType for default type (java.lang) which could cause problems with setting variables, use dedicated type instead
11:56:18,120 ERROR [stderr] (EJB default - 1) java.lang.NullPointerException

11:56:18,131 ERROR [stderr] (EJB default - 1) at org.jbpm.kie.services.impl.bpmn2.DataServiceItemDefinitionHandler.start(DataServiceItemDefinitionHandler.java:42)

11:56:18,139 ERROR [stderr] (EJB default - 1) at org.drools.core.xml.ExtensibleXmlParser.startElement(ExtensibleXmlParser.java:407)

11:56:18,151 ERROR [stderr] (EJB default - 1) at org.apache.xerces.parsers.AbstractSAXParser.startElement(AbstractSAXParser.java:496)

11:56:18,207 ERROR [stderr] (EJB default - 1) at org.apache.xerces.parsers.AbstractXMLDocumentParser.emptyElement(AbstractXMLDocumentParser.java:180)

11:56:18,212 ERROR [stderr] (EJB default - 1) at org.apache.xerces.impl.xs.XMLSchemaValidator.emptyElement(XMLSchemaValidator.java:758)

11:56:18,219 ERROR [stderr] (EJB default - 1) at org.apache.xerces.impl.XMLNSDocumentScannerImpl.scanStartElement(XMLNSDocumentScannerImpl.java:275)

11:56:18,225 ERROR [stderr] (EJB default - 1) at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl$FragmentContentDispatcher.dispatch(XMLDocumentFragmentScannerImpl.java:1653)

11:56:18,326 ERROR [stderr] (EJB default - 1) at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:324)

11:56:18,391 ERROR [stderr] (EJB default - 1) at org.apache.xerces.parsers.XML11Configuration.parse(XML11Configuration.java:845)

11:56:18,422 ERROR [stderr] (EJB default - 1) at org.apache.xerces.parsers.XML11Configuration.parse(XML11Configuration.java:768)

11:56:18,443 ERROR [stderr] (EJB default - 1) at org.apache.xerces.parsers.XMLParser.parse(XMLParser.java:108)

11:56:18,451 ERROR [stderr] (EJB default - 1) at org.apache.xerces.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1196)

11:56:18,459 ERROR [stderr] (EJB default - 1) at org.apache.xerces.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:555)

11:56:18,468 ERROR [stderr] (EJB default - 1) at org.apache.xerces.jaxp.SAXParserImpl.parse(SAXParserImpl.java:289)

11:56:18,481 ERROR [stderr] (EJB default - 1) at org.drools.core.xml.ExtensibleXmlParser.read(ExtensibleXmlParser.java:318)

11:56:18,531 ERROR [stderr] (EJB default - 1) at org.drools.core.xml.ExtensibleXmlParser.read(ExtensibleXmlParser.java:180)

11:56:18,603 ERROR [stderr] (EJB default - 1) at org.jbpm.compiler.xml.XmlProcessReader.read(XmlProcessReader.java:46)

11:56:18,610 ERROR [stderr] (EJB default - 1) at org.jbpm.compiler.ProcessBuilderImpl.addProcessFromXml(ProcessBuilderImpl.java:281)

11:56:18,623 ERROR [stderr] (EJB default - 1) at org.drools.compiler.builder.impl.KnowledgeBuilderImpl.addProcessFromXml(KnowledgeBuilderImpl.java:619)

11:56:18,702 ERROR [stderr] (EJB default - 1) at org.drools.compiler.builder.impl.CompositeKnowledgeBuilderImpl.buildResources(CompositeKnowledgeBuilderImpl.java:176)

11:56:18,708 ERROR [stderr] (EJB default - 1) at org.drools.compiler.builder.impl.CompositeKnowledgeBuilderImpl.build(CompositeKnowledgeBuilderImpl.java:90)

11:56:18,766 ERROR [stderr] (EJB default - 1) at org.drools.compiler.kie.builder.impl.AbstractKieModule.buildKnowledgePackages(AbstractKieModule.java:223)

11:56:18,797 ERROR [stderr] (EJB default - 1) at org.drools.compiler.kie.builder.impl.AbstractKieProject.verify(AbstractKieProject.java:49)

11:56:18,805 ERROR [stderr] (EJB default - 1) at org.drools.compiler.kie.builder.impl.KieBuilderImpl.buildKieProject(KieBuilderImpl.java:212)

11:56:18,812 ERROR [stderr] (EJB default - 1) at org.drools.compiler.kie.builder.impl.KieBuilderImpl.buildKieModule(KieBuilderImpl.java:207)