急！生产环境日志信息，有宕机危险吗？请高手帮助

生产环境下，aix32上的was nd 6.1集群。 4个应用集群里，几乎每天总有一个集群中的应用服务器日志会有以下类似的日志信息，但是没有发生过宕机，这是怎么回事呢？如何处理？危险吗？  请大家帮忙

at com.ebworx.hxb.dcms.corporate.customer.bo.EJSRemoteStatelessCorporateApplicationCustomerEJB_35e9837f.addIndividualGuarantorForExistingCustomer(EJSRemoteStatelessCorporateApplicationCustomerEJB_35e9837f.java:127)
        at com.ebworx.hxb.dcms.corporate.customer.bo._CustomerEJB_Stub.addIndividualGuarantorForExistingCustomer(_CustomerEJB_Stub.java:1491)
        at com.ebworx.hxb.dcms.corporate.web.struts.controller.CustomerAction.addIndividualGuarantor(CustomerAction.java:2366)
        at com.ebworx.hxb.dcms.corporate.web.struts.controller.CustomerAction.doAddProspectCustomer(CustomerAction.java:568)
        ... 40 more
[10/17/11 10:33:32:179 GMT+08:00] 359acb18  ThreadMonitor  W  WSVR0605W: Thread "Servlet.Engine.Transports : 3309" (53a24b39) has been active for 716,012 milliseconds and may be hung.  There are 1 threads in total in the server that may be hung.
[10/17/11 10:33:32:403 GMT+08:00] 79748b39  SRTServletRes  W  WARNING: Cannot set header. Response already committed.
[10/17/11 10:33:44:819 GMT+08:00] 53a24b39  ThreadMonitor  W  WSVR0606W: Thread "Servlet.Engine.Transports : 3309" (53a24b39) was previously reported to be hung but has completed.  It was active for approximately 728,652 milliseconds.  There are 0 threads in total in the server that still may be hung.
[10/17/11 10:33:45:816 GMT+08:00] 468f4b0f SystemOut     O A1
[10/17/11 10:33:45:817 GMT+08:00] 468f4b0f SystemOut     O B1
[10/17/11 10:33:45:818 GMT+08:00] 468f4b0f WebGroup      E SRVE0026E: [Servlet Error]-[]: java.lang.NullPointerException


        at com.ebworx.hxb.dcms.corporate.web.struts.controller.CustomerAction.addIndividualGuarantor(CustomerAction.java:2366)
        at com.ebworx.hxb.dcms.corporate.web.struts.controller.CustomerAction.doAddProspectCustomer(CustomerAction.java:568)
        ... 40 more
[10/17/11 10:33:32:179 GMT+08:00] 359acb18 ThreadMonitor W WSVR0605W: Thread "Servlet.Engine.Transports : 3309" (53a24b39) has been active for 716,012 milliseconds and may be hung.  There are 1 threads in total in the server that may be hung.
[10/17/11 10:33:32:403 GMT+08:00] 79748b39 SRTServletRes W WARNING: Cannot set header. Response already committed.
[10/17/11 10:33:44:819 GMT+08:00] 53a24b39 ThreadMonitor W WSVR0606W: Thread "Servlet.Engine.Transports : 3309" (53a24b39) was previously reported to be hung but has completed.  It was active for approximately 728,652 milliseconds.  There are 0 threads in total in the server that still may be hung.
[10/17/11 10:33:45:816 GMT+08:00] 468f4b0f SystemOut     O A1
[10/17/11 10:33:45:817 GMT+08:00] 468f4b0f SystemOut     O B1
[10/17/11 10:33:45:818 GMT+08:00] 468f4b0f WebGroup      E SRVE0026E: [Servlet Error]-[]: java.lang.NullPointerException
        at java.util.Hashtable.get(Hashtable.java(Compiled Code))
        at com.ibm.icu.text.DecimalFormatSymbols.initialize(DecimalFormatSymbols.java(Compiled Code))


        at com.ebworx.hxb.dcms.corporate.customer.bo.CustomerSessionBean.addNewApplicationForExistingCorporateCustomer(CustomerSessionBean.java:198)
        at com.ebworx.hxb.dcms.corporate.customer.bo.EJSRemoteStatelessCorporateApplicationCustomerEJB_35e9837f.addNewApplicationForExistingCorporateCustomer(EJSRemoteStatelessCorporateApplicationCustomerEJB_35e9837f.java:197)
        at com.ebworx.hxb.dcms.corporate.customer.bo._CustomerEJB_Stub.addNewApplicationForExistingCorporateCustomer(_CustomerEJB_Stub.java:1207)
        at com.ebworx.hxb.dcms.corporate.web.struts.controller.CustomerAction.doAddNewApplicationCorporateCustomer(CustomerAction.java:394)
        ... 41 more
[10/17/11 12:15:32:403 GMT+08:00] 2acb4b1a ThreadMonitor W WSVR0605W: Thread "Servlet.Engine.Transports : 5698" (7abf0b07) has been active for 737,989 milliseconds and may be hung.  There are 1 threads in total in the server that may be hung.
[10/17/11 12:15:32:889 GMT+08:00] 2acb4b1a ThreadMonitor W WSVR0605W: Thread "Servlet.Engine.Transports : 5705" (33a6cb05) has been active for 739,417 milliseconds and may be hung.  There are 2 threads in total in the server that may be hung.
[10/17/11 12:15:34:392 GMT+08:00] 33a6cb05 SRTServletRes W WARNING: Cannot set header. Response already committed.
[10/17/11 12:15:34:405 GMT+08:00] 33a6cb05 ThreadMonitor W WSVR0606W: Thread "Servlet.Engine.Transports : 5705" (33a6cb05) was previously reported to be hung but has completed.  It was active for approximately 741,420 milliseconds.  There are 1 threads in total in the server that still may be hung.
[10/17/11 12:15:35:062 GMT+08:00] 7abf0b07 SRTServletRes W WARNING: Cannot set header. Response already committed.
[10/17/11 12:15:35:077 GMT+08:00] 7abf0b07 ThreadMonitor W WSVR0606W: Thread "Servlet.Engine.Transports : 5698" (7abf0b07) was previously reported to be hung but has completed.  It was active for approximately 740,664 milliseconds.  There are 0 threads in total in the server that still may be hung.


        at com.ebworx.hxb.dcms.corporate.customer.bo.EJSRemoteStatelessCorporateApplicationCustomerEJB_35e9837f.addNewApplicationForExistingCorporateCustomer(EJSRemoteStatelessCorporateApplicationCustomerEJB_35e9837f.java:197)
        at com.ebworx.hxb.dcms.corporate.customer.bo._CustomerEJB_Stub.addNewApplicationForExistingCorporateCustomer(_CustomerEJB_Stub.java:1207)
        at com.ebworx.hxb.dcms.corporate.web.struts.controller.CustomerAction.doAddNewApplicationCorporateCustomer(CustomerAction.java:394)
        ... 41 more
[10/17/11 12:15:32:403 GMT+08:00] 2acb4b1a ThreadMonitor W WSVR0605W: Thread "Servlet.Engine.Transports : 5698" (7abf0b07) has been active for 737,989 milliseconds and may be hung.  There are 1 threads in total in the server that may be hung.
[10/17/11 12:15:32:889 GMT+08:00] 2acb4b1a ThreadMonitor W WSVR0605W: Thread "Servlet.Engine.Transports : 5705" (33a6cb05) has been active for 739,417 milliseconds and may be hung.  There are 2 threads in total in the server that may be hung.
[10/17/11 12:15:34:392 GMT+08:00] 33a6cb05 SRTServletRes W WARNING: Cannot set header. Response already committed.
[10/17/11 12:15:34:405 GMT+08:00] 33a6cb05 ThreadMonitor W WSVR0606W: Thread "Servlet.Engine.Transports : 5705" (33a6cb05) was previously reported to be hung but has completed.  It was active for approximately 741,420 milliseconds.  There are 1 threads in total in the server that still may be hung.
[10/17/11 12:15:35:062 GMT+08:00] 7abf0b07 SRTServletRes W WARNING: Cannot set header. Response already committed.
[10/17/11 12:15:35:077 GMT+08:00] 7abf0b07 ThreadMonitor W WSVR0606W: Thread "Servlet.Engine.Transports : 5698" (7abf0b07) was previously reported to be hung but has completed.  It was active for approximately 740,664 milliseconds.  There are 0 threads in total in the server that still may be hung.
[10/17/11 12:16:21:883 GMT+08:00] 171acb0a WebGroup      E SRVE0026E: [Servlet Error]-[Filter [TrimFilter]: filter is unavailable.]: java.net.SocketException: There is no process to read data written to a pipe.


        at com.ebworx.hxb.dcms.corporate.web.struts.controller.CustomerAction.doAddNewApplicationCorporateCustomer(CustomerAction.java:394)
        ... 41 more
[10/17/11 12:15:32:403 GMT+08:00] 2acb4b1a ThreadMonitor W WSVR0605W: Thread "Servlet.Engine.Transports : 5698" (7abf0b07) has been active for 737,989 milliseconds and may be hung.  There are 1 threads in total in the server that may be hung.
[10/17/11 12:15:32:889 GMT+08:00] 2acb4b1a ThreadMonitor W WSVR0605W: Thread "Servlet.Engine.Transports : 5705" (33a6cb05) has been active for 739,417 milliseconds and may be hung.  There are 2 threads in total in the server that may be hung.
[10/17/11 12:15:34:392 GMT+08:00] 33a6cb05 SRTServletRes W WARNING: Cannot set header. Response already committed.
[10/17/11 12:15:34:405 GMT+08:00] 33a6cb05 ThreadMonitor W WSVR0606W: Thread "Servlet.Engine.Transports : 5705" (33a6cb05) was previously reported to be hung but has completed.  It was active for approximately 741,420 milliseconds.  There are 1 threads in total in the server that still may be hung.
[10/17/11 12:15:35:062 GMT+08:00] 7abf0b07 SRTServletRes W WARNING: Cannot set header. Response already committed.
[10/17/11 12:15:35:077 GMT+08:00] 7abf0b07 ThreadMonitor W WSVR0606W: Thread "Servlet.Engine.Transports : 5698" (7abf0b07) was previously reported to be hung but has completed.  It was active for approximately 740,664 milliseconds.  There are 0 threads in total in the server that still may be hung.
[10/17/11 12:16:21:883 GMT+08:00] 171acb0a WebGroup      E SRVE0026E: [Servlet Error]-[Filter [TrimFilter]: filter is unavailable.]: java.net.SocketException: There is no process to read data written to a pipe.
        at java.net.SocketOutputStream.socketWrite0(Native Method)
        at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java(Compiled Code))


[10/17/11 12:15:32:403 GMT+08:00] 2acb4b1a ThreadMonitor W WSVR0605W: Thread "Servlet.Engine.Transports : 5698" (7abf0b07) has been active for 737,989 milliseconds and may be hung.  There are 1 threads in total in the server that may be hung.
[10/17/11 12:15:32:889 GMT+08:00] 2acb4b1a ThreadMonitor W WSVR0605W: Thread "Servlet.Engine.Transports : 5705" (33a6cb05) has been active for 739,417 milliseconds and may be hung.  There are 2 threads in total in the server that may be hung.
[10/17/11 12:15:34:392 GMT+08:00] 33a6cb05 SRTServletRes W WARNING: Cannot set header. Response already committed.
[10/17/11 12:15:34:405 GMT+08:00] 33a6cb05 ThreadMonitor W WSVR0606W: Thread "Servlet.Engine.Transports : 5705" (33a6cb05) was previously reported to be hung but has completed.  It was active for approximately 741,420 milliseconds.  There are 1 threads in total in the server that still may be hung.
[10/17/11 12:15:35:062 GMT+08:00] 7abf0b07 SRTServletRes W WARNING: Cannot set header. Response already committed.
[10/17/11 12:15:35:077 GMT+08:00] 7abf0b07 ThreadMonitor W WSVR0606W: Thread "Servlet.Engine.Transports : 5698" (7abf0b07) was previously reported to be hung but has completed.  It was active for approximately 740,664 milliseconds.  There are 0 threads in total in the server that still may be hung.
[10/17/11 12:16:21:883 GMT+08:00] 171acb0a WebGroup      E SRVE0026E: [Servlet Error]-[Filter [TrimFilter]: filter is unavailable.]: java.net.SocketException: There is no process to read data written to a pipe.
        at java.net.SocketOutputStream.socketWrite0(Native Method)
        at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java(Compiled Code))
        at java.net.SocketOutputStream.write(SocketOutputStream.java(Compiled Code))
        at com.ibm.ws.io.Stream.write(Stream.java(Compiled Code))收起