EAS7.3的webservice调用context丢失问题

今天客户调用我们的webservice，截至昨天，调用都是正常的，为什么突然就会报这个错误？
PS：login已经login了，而且
后台报错为：
2014-04-17 11:06:24 INFO [con.out] [2014-04-17 11:06:24,672 ERROR RPC-432]someone set ContextClassLoader be null
java.lang.RuntimeException: someone set ContextClassLoader be null
at com.kingdee.bos.rpc.impl.ThreadPool2$Worker.setContextClassLoader(ThreadPool2.java:161)
at com.kingdee.eas.scm.im.inv.ws.util.XMLUtil.getDocumentBuilderFactory(XMLUtil.java:61)
at com.kingdee.eas.scm.im.inv.ws.util.XMLUtil.builderDocument(XMLUtil.java:120)
at com.kingdee.eas.fi.ar.app.webservice.util.BillPropertiesReader.(BillPropertiesReader.java:48)
at com.kingdee.eas.fi.ar.app.webservice.OtherBillFacadeControllerBean._submit(OtherBillFacadeControllerBean.java:129)
at com.kingdee.eas.fi.ar.app.webservice.AbstractOtherBillFacadeControllerBean.submit(AbstractOtherBillFacadeControllerBean.java:43)
at sun.reflect.GeneratedMethodAccessor405.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_SUPPORTS(TxInvokerBean.java:61)
at com.kingdee.bos.transaction.EJBTxFacade.TxInvokerBean_LocalObjectImpl_2.INVOKE_SUPPORTS(Unknown Source)
at com.kingdee.bos.transaction.EJBTransactionProxy.invoke(EJBTransactionProxy.java:179)
at com.kingdee.bos.transaction.EJBTransactionProxy.invoke(EJBTransactionProxy.java:324)
at $Proxy382.submit(Unknown Source)
at com.kingdee.eas.fi.ar.app.webservice.OtherBillFacade.submit(OtherBillFacade.java:44)
at rpc_generate._PROXY_com_1_kingdee_1_eas_1_fi_1_ar_1_app_1_webservice_1_IOtherBillFacade.pi4(Unknown Source)
at rpc_generate._PROXY_com_1_kingdee_1_eas_1_fi_1_ar_1_app_1_webservice_1_IOtherBillFacade.processInvoke(Unknown Source)
at com.kingdee.bos.rpc.impl.ObjectProxy.processInvoke(ObjectProxy.java:177)
at com.kingdee.bos.rpc.impl.RPCService.serviceInvoke(RPCService.java:629)
at com.kingdee.bos.rpc.impl.RPCService.service(RPCService.java:125)
at com.kingdee.bos.rpc.impl.ServiceDispatcher.run(ServiceDispatcher.java:153)
at com.kingdee.bos.rpc.impl.ThreadJob.run(ThreadJob.java:24)
at com.kingdee.bos.rpc.impl.ThreadPool2$Worker.run(ThreadPool2.java:103)
2014-04-17 11:06:24 INFO [con.out] 原解析器:org.apache.xerces.jaxp.DocumentBuilderFactoryImpl