启动tomcat的时候出现报错！！！

2011-3-23 8:48:42 org.apache.catalina.core.AprLifecycleListener init
信息: Loaded APR based Apache Tomcat Native library 1.1.20.
2011-3-23 8:48:42 org.apache.catalina.core.AprLifecycleListener init
信息: APR capabilities: IPv6 [true], sendfile [true], accept filters [false], random [true].
2011-3-23 8:48:42 org.apache.tomcat.util.digester.SetPropertiesRule begin
警告: [SetPropertiesRule]{Server/Service/Engine/Host/Context} Setting property 'debug' to '0' did not find a matching property.
2011-3-23 8:48:42 org.apache.tomcat.util.digester.SetPropertiesRule begin
警告: [SetPropertiesRule]{Server/Service/Engine/Host/Context} Setting property 'debug' to '0' did not find a matching property.
2011-3-23 8:48:42 org.apache.tomcat.util.digester.Digester endElement
严重: End event threw exception
java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.apache.tomcat.util.IntrospectionUtils.callMethod1(IntrospectionUtils.java:804)
at org.apache.tomcat.util.digester.SetNextRule.end(SetNextRule.java:201)
at org.apache.tomcat.util.digester.Digester.endElement(Digester.java:1057)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.endElement(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.AbstractXMLDocumentParser.emptyElement(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanStartElement(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(Unknown Source)
at org.apache.tomcat.util.digester.Digester.parse(Digester.java:1543)
at org.apache.catalina.startup.Catalina.load(Catalina.java:554)
at org.apache.catalina.startup.Catalina.load(Catalina.java:595)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.apache.catalina.startup.Bootstrap.load(Bootstrap.java:262)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:430)
Caused by: java.lang.IllegalArgumentException: addChild: Child name '' is not unique
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:797)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:787)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:607)
... 27 more
2011-3-23 8:48:42 org.apache.catalina.startup.Catalina load
警告: Catalina.start using conf/server.xml: Error at (139, 109) : addChild: Child name '' is not unique
2011-3-23 8:48:42 org.apache.tomcat.util.digester.SetPropertiesRule begin
警告: [SetPropertiesRule]{Server/Service/Engine/Host/Context} Setting property 'debug' to '0' did not find a matching property.
2011-3-23 8:48:42 org.apache.tomcat.util.digester.SetPropertiesRule begin
警告: [SetPropertiesRule]{Server/Service/Engine/Host/Context} Setting property 'debug' to '0' did not find a matching property.
2011-3-23 8:48:42 org.apache.tomcat.util.digester.Digester endElement
严重: End event threw exception
java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.apache.tomcat.util.IntrospectionUtils.callMethod1(IntrospectionUtils.java:804)
at org.apache.tomcat.util.digester.SetNextRule.end(SetNextRule.java:201)
at org.apache.tomcat.util.digester.Digester.endElement(Digester.java:1057)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.endElement(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.AbstractXMLDocumentParser.emptyElement(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanStartElement(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(Unknown Source)
at org.apache.tomcat.util.digester.Digester.parse(Digester.java:1543)
at org.apache.catalina.startup.Catalina.load(Catalina.java:554)
at org.apache.catalina.startup.Catalina.start(Catalina.java:608)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:303)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:431)
Caused by: java.lang.IllegalArgumentException: addChild: Child name '' is not unique
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:797)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:787)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:607)
... 27 more
2011-3-23 8:48:42 org.apache.catalina.startup.Catalina load
警告: Catalina.start using conf/server.xml: Error at (139, 109) : addChild: Child name '' is not unique
2011-3-23 8:48:42 org.apache.catalina.startup.Catalina start
严重: Cannot start server. Server instance is not configured.

把你的tomcat下的conf/server.xml贴出来

似乎是某个xml文件格式错了