Server Tomcat v6.0 Server at localhost failed to start.
This is how error happened.Now i am using Eclipse Indigo integrated with apache tomcat 6.0 and also changed the default port to 9090.

    Jul 16, 2011 11:12:06 AM org.apache.tomcat.util.digester.SetPropertiesRule begin
    WARNING: [SetPropertiesRule]{Server/Service/Engine/Host/Context} Setting property      'source' to 'org.eclipse.jst.jee.server:uu' did not find a matching property.
    Jul 16, 2011 11:12:06 AM org.apache.catalina.core.AprLifecycleListener init
    INFO: The APR based Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path: C:\Program Files\Java\jre1.7.0\bin;.;C:\WINDOWS\Sun\Java\bin;C:\WINDOWS\system32;C:\WINDOWS;C:/Program Files/Java/jre1.7.0/bin/client;C:/Program Files/Java/jre1.7.0/bin;C:/Program Files/Java/jre1.7.0/lib/i386;D:\oracle\ora90\bin;D:\oracle\ora90\Apache\Perl\5.00503\bin\mswin32-x86;C:\Program Files\Oracle\jre\1.1.8\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\Program Files\Intel\DMIX;C:\Program Files\Diskeeper Corporation\Diskeeper\;C:\Program Files\Microsoft SQL Server\90\Tools\binn\;C:\Program Files\Java\jdk1.7.0\bin;C:\Program Files\Apache Software Foundation\Apache Tomcat 6.0.14;C:\Program Files\QuickTime\QTSystem\;E:\eclipse;
     Jul 16, 2011 11:12:06 AM org.apache.coyote.http11.Http11Protocol init
     INFO: Initializing Coyote HTTP/1.1 on http-9080
     Jul 16, 2011 11:12:06 AM org.apache.catalina.startup.Catalina load 
     INFO: Initialization processed in 539 ms
     Jul 16, 2011 11:12:06 AM org.apache.catalina.core.StandardService start
    INFO: Starting service Catalina
      Jul 16, 2011 11:12:06 AM org.apache.catalina.core.StandardEngine start
    INFO: Starting Servlet Engine: Apache Tomcat/6.0.18
    Jul 16, 2011 11:12:06 AM org.apache.tomcat.util.modeler.Registry registerComponent
     SEVERE: Null component Catalina:type=JspMonitor,name=jsp,WebModule=//localhost/uu,J2EEApplication=none,J2EEServer=none
       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.catalina.startup.Bootstrap.start(Bootstrap.java:288)
	at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:413)
        Caused by: java.lang.UnsupportedClassVersionError: yy/ii : Unsupported major.minor version 51.0 (unable to load class yy.ii)
	at     org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:1851)                                                                                             at     org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:890)
	at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1354)
	at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1233)
	at org.apache.catalina.startup.WebAnnotationSet.loadApplicationServletAnnotations(WebAnnotationSet.java:108)
	at org.apache.catalina.startup.WebAnnotationSet.loadApplicationAnnotations(WebAnnotationSet.java:58)
	at org.apache.catalina.startup.ContextConfig.applicationAnnotationsConfig(ContextConfig.java:297)
	at org.apache.catalina.startup.ContextConfig.start(ContextConfig.java:1068)
	at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:261)
	at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:117)
	at org.apache.catalina.core.StandardContext.start(StandardContext.java:4252)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
	at org.apache.catalina.core.StandardHost.start(StandardHost.java:719)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
	at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
	at org.apache.catalina.core.StandardService.start(StandardService.java:516)
	at org.apache.catalina.core.StandardServer.start(StandardServer.java:710)
	at org.apache.catalina.startup.Catalina.start(Catalina.java:578)
	... 6 more

Server Tomcat v6.0 Server at localhost failed to start.
===

This is how error happened.Now i am using Eclipse Indigo integrated with apache tomcat 6.0 and also changed the default port to 9090.

    Jul 16, 2011 11:12:06 AM org.apache.tomcat.util.digester.SetPropertiesRule begin
    WARNING: [SetPropertiesRule]{Server/Service/Engine/Host/Context} Setting property      'source' to 'org.eclipse.jst.jee.server:uu' did not find a matching property.
    Jul 16, 2011 11:12:06 AM org.apache.catalina.core.AprLifecycleListener init
    INFO: The APR based Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path: C:\Program Files\Java\jre1.7.0\bin;.;C:\WINDOWS\Sun\Java\bin;C:\WINDOWS\system32;C:\WINDOWS;C:/Program Files/Java/jre1.7.0/bin/client;C:/Program Files/Java/jre1.7.0/bin;C:/Program Files/Java/jre1.7.0/lib/i386;D:\oracle\ora90\bin;D:\oracle\ora90\Apache\Perl\5.00503\bin\mswin32-x86;C:\Program Files\Oracle\jre\1.1.8\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\Program Files\Intel\DMIX;C:\Program Files\Diskeeper Corporation\Diskeeper\;C:\Program Files\Microsoft SQL Server\90\Tools\binn\;C:\Program Files\Java\jdk1.7.0\bin;C:\Program Files\Apache Software Foundation\Apache Tomcat 6.0.14;C:\Program Files\QuickTime\QTSystem\;E:\eclipse;
     Jul 16, 2011 11:12:06 AM org.apache.coyote.http11.Http11Protocol init
     INFO: Initializing Coyote HTTP/1.1 on http-9080
     Jul 16, 2011 11:12:06 AM org.apache.catalina.startup.Catalina load 
     INFO: Initialization processed in 539 ms
     Jul 16, 2011 11:12:06 AM org.apache.catalina.core.StandardService start
    INFO: Starting service Catalina
      Jul 16, 2011 11:12:06 AM org.apache.catalina.core.StandardEngine start
    INFO: Starting Servlet Engine: Apache Tomcat/6.0.18
    Jul 16, 2011 11:12:06 AM org.apache.tomcat.util.modeler.Registry registerComponent
     SEVERE: Null component Catalina:type=JspMonitor,name=jsp,WebModule=//localhost/uu,J2EEApplication=none,J2EEServer=none
       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.catalina.startup.Bootstrap.start(Bootstrap.java:288)
	at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:413)
        Caused by: java.lang.UnsupportedClassVersionError: yy/ii : Unsupported major.minor version 51.0 (unable to load class yy.ii)
	at     org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:1851)                                                                                             at     org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:890)
	at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1354)
	at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1233)
	at org.apache.catalina.startup.WebAnnotationSet.loadApplicationServletAnnotations(WebAnnotationSet.java:108)
	at org.apache.catalina.startup.WebAnnotationSet.loadApplicationAnnotations(WebAnnotationSet.java:58)
	at org.apache.catalina.startup.ContextConfig.applicationAnnotationsConfig(ContextConfig.java:297)
	at org.apache.catalina.startup.ContextConfig.start(ContextConfig.java:1068)
	at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:261)
	at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:117)
	at org.apache.catalina.core.StandardContext.start(StandardContext.java:4252)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
	at org.apache.catalina.core.StandardHost.start(StandardHost.java:719)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
	at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
	at org.apache.catalina.core.StandardService.start(StandardService.java:516)
	at org.apache.catalina.core.StandardServer.start(StandardServer.java:710)
	at org.apache.catalina.startup.Catalina.start(Catalina.java:578)
	... 6 more
