今天在将geoserver部署到tomcat时发现无法运行，费了很大的劲发现是gvSIG将JAI相关的jar包导入了jre里面，版本不一样发生了冲突。后来将geoserver下面的jai覆盖jdk和jre中的，问题就解决了。
This problem is solved just now although I cannot tell why it casued and solved. I replace the jai related jars in C:/Program Files/Java/jdk1.6.0_24/jre/lib/ext folder and C:/Program Files/Java/jre6/lib/ext folder by the jai related jars in geoserver, such as E:/Program Files/Servers/apache-tomcat-6.0.18/webapps/geoserver/WEB-INF/lib
BTW, the jai related jars are jai_codec-1.1.3.jar, jai_core-1.1.3.jar and jai_imageio-1.1.jar
startup.HostConfig.deployWAR(HostConfig.java:830)
at org.apache.catalina.startup.HostConfig.deployWARs(HostConfig.java:719)
at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:490)
at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1149)
at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:311)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:117)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1053)
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)
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)
log4j:WARN File option not set for appender [geoserverlogfile].
log4j:WARN Are you using FileAppender instead of ConsoleAppender?