有没有人遇到我这样的问题帮助解决下！

    有没有人遇到我这样的问题帮助解决下！
    tomcat服务器 后台 老是 报 下面的 3个错误，界面有时就找不到了，但是刷新 后有好用，再就是 有时 图片显示 不全，刷新后又好了（说明：在一个tomcat5.5.7下配置了2个应用）
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2007-12-27 12:23:54 org.apache.catalina.connector.CoyoteAdapter service
严重: An exception or error occurred in the container during the request processing
java.lang.NullPointerException
at org.apache.tomcat.util.http.MimeHeaders.clear(MimeHeaders.java:130)
at org.apache.coyote.Response.reset(Response.java:289)
at org.apache.catalina.connector.Response.reset(Response.java:653)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:135)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:108)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:151)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:874)
at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:665)
at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:528)
at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:81)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:689)
at java.lang.Thread.run(Unknown Source)
2007-12-27 12:23:54 org.apache.coyote.http11.Http11Processor process
-------------------------------
2007-12-27 12:23:54 org.apache.coyote.http11.Http11Processor process
严重: Error finishing response
java.lang.NullPointerException
at org.apache.tomcat.util.http.MimeHeaders.setValue(MimeHeaders.java:267)
at org.apache.coyote.http11.Http11Processor.prepareResponse(Http11Processor.java:1597)
at org.apache.coyote.http11.Http11Processor.action(Http11Processor.java:967)
at org.apache.coyote.Response.action(Response.java:181)
at org.apache.coyote.http11.InternalOutputBuffer.endRequest(InternalOutputBuffer.java:389)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:911)
at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:665)
at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:528)
at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:81)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:689)
at java.lang.Thread.run(Unknown Source)
2007-12-27 12:23:54 org.apache.coyote.http11.Http11Processor process
---------------------
严重: Error reading request, ignored
java.lang.NullPointerException
at org.apache.tomcat.util.http.MimeHeaders.clear(MimeHeaders.java:130)
at org.apache.coyote.Response.recycle(Response.java:579)
at org.apache.coyote.http11.InternalOutputBuffer.nextRequest(InternalOutputBuffer.java:356)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:934)
at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:665)
at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:528)
at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:81)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:689)
at java.lang.Thread.run(Unknown Source)
2007-12-27 12:23:54 org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler processConnection
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