Hi all,
I am getting an exception on runtime,

19:25:40,515 INFO [STDOUT] javax.ejb.TransactionRolledbackLocalException: Application deadlock detected, resource=org.jboss.ejb.plugins.lock.QueuedPessimisticEJBLock@e8e754, bean=EmployeePersonal, id=com.quark.hrms.employeemanagement.ejb.entity.employeepersonal.EmployeePersonalPK@276, refs=2, tx=TransactionImpl:XidImpl[FormatId=257, GlobalId=Keerthikar/1711, BranchQual=, localId=1711], synched=Thread[RMI TCP Connection(66)-10.91.194.24,5,RMI Runtime], timeout=5000, queue=[], holder=TransactionImpl:XidImpl[FormatId=257, GlobalId=Keerthikar/1713, BranchQual=, localId=1713], waitingResource=org.jboss.ejb.plugins.lock.QueuedPessimisticEJBLock@ab719b, bean=Employee, id=com.quark.hrms.employeemanagement.ejb.entity.employee.EmployeePK@276, refs=2, tx=TransactionImpl:XidImpl[FormatId=257, GlobalId=Keerthikar/1713, BranchQual=, localId=1713], synched=null, timeout=5000, queue=[TXLOCK waitingTx=TransactionImpl:XidImpl[FormatId=257, GlobalId=Keerthikar/1711, BranchQual=, localId=1711] id=0 thread=Thread[RMI TCP Connection(61)-10.91.194.24,5,RMI Runtime] queued=true], waitingResourceHolder=TransactionImpl:XidImpl[FormatId=257, GlobalId=Keerthikar/1713, BranchQual=, localId=1713]; CausedByException is:
Application deadlock detected, resource=org.jboss.ejb.plugins.lock.QueuedPessimisticEJBLock@e8e754, bean=EmployeePersonal, id=com.quark.hrms.employeemanagement.ejb.entity.employeepersonal.EmployeePersonalPK@276, refs=2, tx=TransactionImpl:XidImpl[FormatId=257, GlobalId=Keerthikar/1711, BranchQual=, localId=1711], synched=Thread[RMI TCP Connection(66)-10.91.194.24,5,RMI Runtime], timeout=5000, queue=[], holder=TransactionImpl:XidImpl[FormatId=257, GlobalId=Keerthikar/1713, BranchQual=, localId=1713], waitingResource=org.jboss.ejb.plugins.lock.QueuedPessimisticEJBLock@ab719b, bean=Employee, id=com.quark.hrms.employeemanagement.ejb.entity.employee.EmployeePK@276, refs=2, tx=TransactionImpl:XidImpl[FormatId=257, GlobalId=Keerthikar/1713, BranchQual=, localId=1713], synched=null, timeout=5000, queue=[TXLOCK waitingTx=TransactionImpl:XidImpl[FormatId=257, GlobalId=Keerthikar/1711, BranchQual=, localId=1711] id=0 thread=Thread[RMI TCP Connection(61)-10.91.194.24,5,RMI Runtime] queued=true], waitingResourceHolder=TransactionImpl:XidImpl[FormatId=257, GlobalId=Keerthikar/1713, BranchQual=, localId=1713]
19:25:40,531 INFO [STDOUT] at org.jboss.ejb.plugins.AbstractTxInterceptor.invokeNext(AbstractTxInterceptor.java:232)
19:25:40,531 INFO [STDOUT] at org.jboss.ejb.plugins.TxInterceptorCMT.runWithTransactions(TxInterceptorCMT.java:316)
19:25:40,531 INFO [STDOUT] at org.jboss.ejb.plugins.TxInterceptorCMT.invoke(TxInterceptorCMT.java:149)
19:25:40,531 INFO [STDOUT] at org.jboss.ejb.plugins.SecurityInterceptor.invoke(SecurityInterceptor.java:128)
19:25:40,531 INFO [STDOUT] at org.jboss.ejb.plugins.LogInterceptor.invoke(LogInterceptor.java:191)
19:25:40,531 INFO [STDOUT] at org.jboss.ejb.plugins.ProxyFactoryFinderInterceptor.invoke(ProxyFactoryFinderInterceptor.java:122)
19:25:40,531 INFO [STDOUT] at org.jboss.ejb.EntityContainer.internalInvoke(EntityContainer.java:514)
19:25:40,531 INFO [STDOUT] at org.jboss.ejb.Container.invoke(Container.java:859)
19:25:40,531 INFO [STDOUT] at org.jboss.ejb.plugins.local.BaseLocalProxyFactory.invoke(BaseLocalProxyFactory.java:413)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.plugins.local.EntityProxy.invoke(EntityProxy.java:44)
19:25:40,546 INFO [STDOUT] at $Proxy501.getEmployeePersonalDO(Unknown Source)
19:25:40,546 INFO [STDOUT] at com.quark.hrms.employeemanagement.ejb.session.employeemanager.EmployeeManager.getEmployeePersonalDO(EmployeeManager.java:224)
19:25:40,546 INFO [STDOUT] at sun.reflect.GeneratedMethodAccessor93.invoke(Unknown Source)
19:25:40,546 INFO [STDOUT] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
19:25:40,546 INFO [STDOUT] at java.lang.reflect.Method.invoke(Method.java:324)
19:25:40,546 INFO [STDOUT] at org.jboss.invocation.Invocation.performCall(Invocation.java:345)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.StatelessSessionContainer$ContainerInterceptor.invoke(StatelessSessionContainer.java:214)
19:25:40,546 INFO [STDOUT] at org.jboss.resource.connectionmanager.CachedConnectionInterceptor.invoke(CachedConnectionInterceptor.java:185)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.plugins.StatelessSessionInstanceInterceptor.invoke(StatelessSessionInstanceInterceptor.java:113)
19:25:40,546 INFO [STDOUT] at org.jboss.webservice.server.ServiceEndpointInterceptor.invoke(ServiceEndpointInterceptor.java:51)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.plugins.CallValidationInterceptor.invoke(CallValidationInterceptor.java:48)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.plugins.AbstractTxInterceptor.invokeNext(AbstractTxInterceptor.java:105)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.plugins.TxInterceptorCMT.runWithTransactions(TxInterceptorCMT.java:316)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.plugins.TxInterceptorCMT.invoke(TxInterceptorCMT.java:149)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.plugins.SecurityInterceptor.invoke(SecurityInterceptor.java:128)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.plugins.LogInterceptor.invoke(LogInterceptor.java:191)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.plugins.ProxyFactoryFinderInterceptor.invoke(ProxyFactoryFinderInterceptor.java:122)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.SessionContainer.internalInvoke(SessionContainer.java:624)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.Container.invoke(Container.java:859)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.plugins.local.BaseLocalProxyFactory.invoke(BaseLocalProxyFactory.java:413)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.plugins.local.StatelessSessionProxy.invoke(StatelessSessionProxy.java:82)
19:25:40,546 INFO [STDOUT] at $Proxy580.getEmployeePersonalDO(Unknown Source)
19:25:40,546 INFO [STDOUT] at com.quark.hrms.newperformanceappraisal.ejb.session.individualgoalmanager.IndividualGoalManager.getEmployeeDetailsDO(IndividualGoalManager.java:491)
19:25:40,546 INFO [STDOUT] at sun.reflect.GeneratedMethodAccessor101.invoke(Unknown Source)
19:25:40,546 INFO [STDOUT] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
19:25:40,546 INFO [STDOUT] at java.lang.reflect.Method.invoke(Method.java:324)
19:25:40,546 INFO [STDOUT] at org.jboss.invocation.Invocation.performCall(Invocation.java:345)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.StatelessSessionContainer$ContainerInterceptor.invoke(StatelessSessionContainer.java:214)
19:25:40,546 INFO [STDOUT] at org.jboss.resource.connectionmanager.CachedConnectionInterceptor.invoke(CachedConnectionInterceptor.java:185)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.plugins.StatelessSessionInstanceInterceptor.invoke(StatelessSessionInstanceInterceptor.java:113)
19:25:40,546 INFO [STDOUT] at org.jboss.webservice.server.ServiceEndpointInterceptor.invoke(ServiceEndpointInterceptor.java:51)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.plugins.CallValidationInterceptor.invoke(CallValidationInterceptor.java:48)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.plugins.AbstractTxInterceptor.invokeNext(AbstractTxInterceptor.java:105)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.plugins.TxInterceptorCMT.runWithTransactions(TxInterceptorCMT.java:316)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.plugins.TxInterceptorCMT.invoke(TxInterceptorCMT.java:149)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.plugins.SecurityInterceptor.invoke(SecurityInterceptor.java:128)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.plugins.LogInterceptor.invoke(LogInterceptor.java:191)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.plugins.ProxyFactoryFinderInterceptor.invoke(ProxyFactoryFinderInterceptor.java:122)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.SessionContainer.internalInvoke(SessionContainer.java:624)
19:25:40,546 INFO [STDOUT] at org.jboss.ejb.Container.invoke(Container.java:859)
19:25:40,546 INFO [STDOUT] at sun.reflect.GeneratedMethodAccessor87.invoke(Unknown Source)
19:25:40,546 INFO [STDOUT] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
19:25:40,546 INFO [STDOUT] at java.lang.reflect.Method.invoke(Method.java:324)
19:25:40,546 INFO [STDOUT] at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:141)
19:25:40,546 INFO [STDOUT] at org.jboss.mx.server.Invocation.dispatch(Invocation.java:80)
19:25:40,546 INFO [STDOUT] at org.jboss.mx.server.Invocation.invoke(Invocation.java:72)
19:25:40,546 INFO [STDOUT] at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:236)
19:25:40,546 INFO [STDOUT] at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:642)
19:25:40,546 INFO [STDOUT] at org.jboss.invocation.jrmp.server.JRMPInvoker$MBeanServerAction.invoke(JRMPInvoker.java:775)
19:25:40,546 INFO [STDOUT] at org.jboss.invocation.jrmp.server.JRMPInvoker.invoke(JRMPInvoker.java:382)
19:25:40,546 INFO [STDOUT] at sun.reflect.GeneratedMethodAccessor86.invoke(Unknown Source)
19:25:40,546 INFO [STDOUT] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
19:25:40,546 INFO [STDOUT] at java.lang.reflect.Method.invoke(Method.java:324)
19:25:40,546 INFO [STDOUT] at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:261)
19:25:40,546 INFO [STDOUT] at sun.rmi.transport.Transport$1.run(Transport.java:148)
19:25:40,546 INFO [STDOUT] at java.security.AccessController.doPrivileged(Native Method)
19:25:40,546 INFO [STDOUT] at sun.rmi.transport.Transport.serviceCall(Transport.java:144)
19:25:40,546 INFO [STDOUT] at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:460)
19:25:40,546 INFO [STDOUT] at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:701)
19:25:40,546 INFO [STDOUT] at java.lang.Thread.run(Thread.java:534)

Anyone , pls tell me the reason why this exception occurs.
All suggestions are welcome.