Error invoking method getPrincipalName

org.apache.ojb.broker.PersistenceBrokerException: Error invoking method getPrincipalName
    at org.apache.ojb.broker.core.proxy.AbstractIndirectionHandler.invoke(Unknown Source)
    at za.org.kuali.kfs.mm.businessobject.Profile$$EnhancerByCGLIB$$f4ec489.getPrincipalName(<generated>)
    at za.org.kuali.kfs.mm.fp.service.impl.KfsInternalBillingService.initInternalBillingDocument(KfsInternalBillingService.java:121)
    at za.org.kuali.kfs.mm.fp.service.impl.KfsInternalBillingService.doCreateAndSubmit(KfsInternalBillingService.java:95)
    at za.org.kuali.kfs.mm.fp.service.impl.KfsInternalBillingService.submitInternalBillingDocument(KfsInternalBillingService.java:69)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:318)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:110)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
    at com.sun.proxy.$Proxy423.submitInternalBillingDocument(Unknown Source)
    at za.org.kuali.kfs.mm.service.impl.PickVerifyServiceImpl.processInternalBilling(PickVerifyServiceImpl.java:128)
    at za.org.kuali.kfs.mm.service.impl.PickVerifyServiceImpl.processInternalBilling(PickVerifyServiceImpl.java:94)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:318)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:110)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
    at com.sun.proxy.$Proxy503.processInternalBilling(Unknown Source)
    at za.org.kuali.kfs.mm.document.kew.PickVerifyPostProcessor.afterProcess(PickVerifyPostProcessor.java:26)
    at org.kuali.rice.kew.engine.StandardWorkflowEngine.notifyPostProcessorAfterProcess(StandardWorkflowEngine.java:683)
    at org.kuali.rice.kew.engine.StandardWorkflowEngine.notifyPostProcessorAfterProcess(StandardWorkflowEngine.java:666)
    at org.kuali.rice.kew.engine.StandardWorkflowEngine.process(StandardWorkflowEngine.java:163)
    at org.kuali.rice.kew.impl.document.DocumentProcessingQueueImpl.processWithOptions(DocumentProcessingQueueImpl.java:66)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:318)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:110)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
    at com.sun.proxy.$Proxy200.processWithOptions(Unknown Source)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.kuali.rice.ksb.messaging.MessageServiceInvoker.invokeService(MessageServiceInvoker.java:157)
    at org.kuali.rice.ksb.messaging.MessageServiceInvoker$1.doInTransaction(MessageServiceInvoker.java:72)
    at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:130)
    at org.kuali.rice.ksb.messaging.MessageServiceInvoker.run(MessageServiceInvoker.java:67)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException
    at sun.reflect.GeneratedMethodAccessor853.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    ... 56 more