工作流执行自动活动时出错.源活动【部门经理审批】

EAS7.0版本，触发流程后流程自动挂起，查看日志报错如下，求哪位大神能指点指点，拜托拜托：
异常内码WFE_INVOKETOOLERROR
异常类型:中断
子系统:WORKFLOW
null
工作流自动任务执行时发生错误
发生场景:
工作流执行自动节点(包括函数节点,服务节点,脚本节点,单据转换节点,自动节点)时发生错误
建议解决办法:
阅读具体出错信息并修改
Caused by: com.kingdee.bos.workflow.WfException :
trans error!
Caused exception message is: null
java.lang.NullPointerException
at java.net.URLEncoder.encode(URLEncoder.java:227)
at com.kingdee.eas.tao.MessagePush.execute(MessagePush.java:87)
at com.kingdee.bos.workflow.enactment.WfEventService.raiseAssignmentEvent(WfEventService.java:109)
at com.kingdee.bos.workflow.enactment.WfActivity.createAssignments(WfActivity.java:2070)
at com.kingdee.bos.workflow.enactment.WfActivity.assignCountersign(WfActivity.java:2462)
at com.kingdee.bos.workflow.enactment.WfActivity.assignCountersign(WfActivity.java:2390)
at com.kingdee.bos.workflow.enactment.WfActivity.assignToPerformers(WfActivity.java:1596)
at com.kingdee.bos.workflow.enactment.WfActivity.handleBindedFunction(WfActivity.java:2548)
at com.kingdee.bos.workflow.enactment.WfActivity.init(WfActivity.java:260)
at com.kingdee.bos.workflow.enactment.WfActivity.init(WfActivity.java:231)
at com.kingdee.bos.workflow.enactment.WfProcess.transInternal(WfProcess.java:2621)
at com.kingdee.bos.workflow.enactment.WfProcess.trans(WfProcess.java:2275)
at com.kingdee.bos.workflow.enactment.WfProcess.trans(WfProcess.java:2203)
at com.kingdee.bos.workflow.enactment.WfProcess.transNext(WfProcess.java:2105)
at com.kingdee.bos.workflow.enactment.WfActivity.completeInternal(WfActivity.java:927)
at com.kingdee.bos.workflow.enactment.WfActivity.completeInternal(WfActivity.java:740)
at com.kingdee.bos.workflow.enactment.WfActivity.complete(WfActivity.java:1130)
at com.kingdee.bos.workflow.enactment.ToolActivityRunner.start(ToolActivityRunner.java:94)
at com.kingdee.bos.workflow.enactment.WfActivity.activate(WfActivity.java:1218)
at com.kingdee.bos.workflow.enactment.WfProcess.transInternal(WfProcess.java:2638)
at com.kingdee.bos.workflow.enactment.WfEngine.trans(WfEngine.java:1178)
at com.kingdee.bos.workflow.enactment.WfEngine.transSupport(WfEngine.java:1142)
at sun.reflect.GeneratedMethodAccessor1291.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:618)
at com.kingdee.bos.workflow.util.InvocationExecutor.execute(InvocationExecutor.java:28)
at com.kingdee.bos.workflow.transaction.WfTxInvoker.invoke(WfTxInvoker.java:33)
at sun.reflect.GeneratedMethodAccessor112.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:618)
at com.kingdee.bos.workflow.metas.InvokeMethodDelegateControllerBean.invoke(InvokeMethodDelegateControllerBean.java:76)
at com.kingdee.bos.workflow.metas.InvokeMethodDelegateControllerBean._invokeRequired(InvokeMethodDelegateControllerBean.java:30)
at com.kingdee.bos.workflow.metas.AbstractInvokeMethodDelegateControllerBean.invokeRequired(AbstractInvokeMethodDelegateControllerBean.java:46)
at sun.reflect.GeneratedMethodAccessor822.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:618)
at com.kingdee.bos.transaction.EJBTxFacade.TxInvokerBean.invoke(TxInvokerBean.java:116)
at com.kingdee.bos.transaction.EJBTxFacade.TxInvokerBean.INVOKE_REQUIRED(TxInvokerBean.java:57)
at com.kingdee.bos.transaction.EJBTxFacade.TxInvokerBean_LocalObjectImpl_2.INVOKE_REQUIRED(Unknown Source)
at com.kingdee.bos.transaction.EJBTransactionProxy.invoke(EJBTransactionProxy.java:171)
at com.kingdee.bos.transaction.EJBTransactionProxy.invoke(EJBTransactionProxy.java:324)
at $Proxy171.invokeRequired(Unknown Source)
at com.kingdee.bos.workflow.metas.InvokeMethodDelegate.invokeRequired(InvokeMethodDelegate.java:61)
at sun.reflect.GeneratedMethodAccessor821.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:618)
at com.kingdee.bos.ResponseInvocationHandler.invoke(ResponseInvocationHandler.java:193)
at $Proxy170.invokeRequired(Unknown Source)
at com.kingdee.bos.workflow.transaction.WfTxHelper.invokeRequired(WfTxHelper.java:72)
at com.kingdee.bos.workflow.enactment.thread.TransRunner.transInWfTx(TransRunner.java:56)
at com.kingdee.bos.workflow.enactment.thread.TransRunner.run(TransRunner.java:35)
at com.kingdee.bos.util.ThreadPool$Worker.run(ThreadPool.java:164)