[pgsql-jp: 28511] データベースへのアクセスに失敗しました

[SyuOokawa]

始めて投稿致します。
PostgreSQL稼動中に結構頻繁に下記のエラーメッセージが出てきます。

環境
RedHatLinux7.2
PostgreSQL7.1
Apache_1.3.26
J2SDK-1_4_0_01
Tomcat-4.0

エラー内容：-------------------------------ここから-結構長いです
データベースへのアクセスに失敗しました
An I/O error has occured while flushing the output - Exception:
 java.net.SocketException: Socket closed Stack Trace:
 java.net.SocketException:
 Socket closed at java.net.SocketOutputStream.socketWrite0(Native Method)
 at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:92)
 at java.net.SocketOutputStream.write(SocketOutputStream.java:126)
 at java.io.BufferedOutputStream.flushBuffer(BufferedOutputStream.java:69)
 at java.io.BufferedOutputStream.flush(BufferedOutputStream.java:127)
 at org.postgresql.PG_Stream.flush(Unknown Source)
 at org.postgresql.Connection.ExecSQL(Unknown Source)
 at org.postgresql.jdbc2.Statement.execute(Unknown Source)
 at org.postgresql.jdbc2.Statement.executeQuery(Unknown Source)
 at org.postgresql.jdbc2.PreparedStatement.executeQuery(Unknown Source)
 at jp.co.jamco.subcontractor.business.FactoryLoginCheck.getLoginStatus(FactoryLoginCheck.java:71)
 at jp.co.jamco.subcontractor.action.FactoryLoginAction.perform(FactoryLoginAction.java:53)
 at org.apache.struts.action.ActionServlet.processActionPerform(ActionServlet.java:1787)
 at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1586)
 at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:510)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:760)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:243)
 at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
 at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
 at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:190)
 at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
 at org.apache.catalina.valves.CertificatesValve.invoke(CertificatesValve.java:246)
 at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
 at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
 at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
 at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2347)
 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180)
 at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
 at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:170)
 at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:170)
 at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
 at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:468)
 at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
 at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
 at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174)
 at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
 at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
 at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
 at org.apache.ajp.tomcat4.Ajp13Processor.process(Ajp13Processor.java:458)
 at org.apache.ajp.tomcat4.Ajp13Processor.run(Ajp13Processor.java:551)
 at java.lang.Thread.run(Thread.java:536) End of Stack Trace  
エラー内容：-------------------------------ここまで

もし、知ってる方がいらしたら教えて頂きたいのですが、
すみませんが、よろしくお願い致します。

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Name:SyuOokawa
Mail:post ＠ sic-sys.net
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