How to resolve ORA-00060 : Deadlock detected while waiting for resource exception in JBPM?

Issue

• Following error messages like Deadlock detected while waiting for resource and No active JTA transaction on joinTransaction call are being shown in the JBPM servers logs.

...
Caused by: java.sql.SQLException: ORA-00060: deadlock detected while waiting for resource
                at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:440) [ojdbc6-11.2.0.2.jar:11.2.0.2.0]
                at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:396) [ojdbc6-11.2.0.2.jar:11.2.0.2.0]
...
...
Caused by: javax.persistence.TransactionRequiredException: No active JTA transaction on joinTransaction call
                at org.hibernate.ejb.AbstractEntityManagerImpl.joinTransaction(AbstractEntityManagerImpl.java:1233) [hibernate-entitymanager-4.2.18.Final-redhat-2.jar:4.2.18.Final-redhat-2]
                at org.hibernate.ejb.AbstractEntityManagerImpl.joinTransaction(AbstractEntityManagerImpl.java:1183) [hibernate-entitymanager-4.2.18.Final-redhat-2.jar:4.2.18.Final-redhat-2]
                at org.drools.persistence.jpa.JpaPersistenceContext.joinTransaction(JpaPersistenceContext.java:87) [drools-persistence-jpa-6.2.0.Final-redhat-9.jar:6.2.0.Final-redhat-9]
                at org.drools.persistence.SingleSessionCommandService$TransactionInterceptor.execute(SingleSessionCommandService.java:519) [drools-persistence-jpa-6.2.0.Final-redhat-9.jar:6.2.0.Final-redhat-9]
...