404内部Tomcat出错，更换tomcat，但深层原因是什么？

页面：
HTTP Status 404 - /shiyan/

--------------------------------------------

type Status report

message /shiyan/

description The requested resource (/shiyan/) is not available.
控制台：
1.严重: Exception sending context initialized event to listener instance ofclass org.springframework.web.context.ContextLoaderListener
org.springframework.beans.factory.BeanCreationException:Error creating bean with name 'sessionFactory' defined inServletContext resource [/WEB-INF/applicationContext.xml]: Invocationof init method failed; nested exception isorg.hibernate.HibernateException: Unable to instantiate defaulttuplizer [org.hibernate.tuple.entity.PojoEntityTuplizer]

2.Causedby: org.hibernate.HibernateException: Unable to instantiate defaulttuplizer [org.hibernate.tuple.entity.PojoEntityTuplizer]
3.Caused by: java.lang.reflect.InvocationTargetException
4.Causedby: java.lang.NoSuchMethodError:org.objectweb.asm.ClassVisitor.visit(IILjava/lang/String;Ljava/lang/String;[Ljava/lang/String;Ljava/lang/String;)V

5.2011-6-24 17:05:44 org.apache.catalina.core.StandardContext start
严重: Error listenerStart
2011-6-24 17:05:44 org.apache.catalina.core.StandardContext start
严重: Context [/bspdemo] startup failed due to previous errors
2011-6-24 17:05:44 org.apache.catalina.core.ApplicationContext log
信息: Closing Spring root WebApplicationContext
2011-6-24 17:05:46 org.apache.catalina.loader.WebappClassLoader loadClass
信息: Illegal access: this web application instance has been stoppedalready.? Could not load java.net.HttpURLConnection.? The eventualfollowing stack trace is caused by an error thrown for debuggingpurposes as well as to attempt to terminate the thread which caused theillegal access, and has no functional impact.
java.lang.IllegalStateException

6.信息: Illegal access: this web application instance has been stoppedalready.? Could not load org.apache.xerces.impl.dtd.XMLNotationDecl.?The eventual following stack trace is caused by an error thrown fordebugging purposes as well as to attempt to terminate the thread whichcaused the illegal access, and has no functional impact.

7.严重: Error deploying web application directory shiyan
java.lang.NoClassDefFoundError: org/apache/xerces/impl/dtd/XMLNotationDecl

8.严重: Error deploying web application directory Show3DHouse
java.lang.NoClassDefFoundError: org/apache/xerces/impl/dtd/XMLNotationDecl
9.严重: Error deploying web application directory Unity3DHouse
java.lang.NoClassDefFoundError: org/apache/xerces/impl/dtd/XMLNotationDec

我的异常网推荐解决方案：org.springframework.beans.factory.BeanCreationException:,http://www.myexception.cn/j2ee/10759.html
我的异常网推荐解决方案：Unable to instantiate default tuplizer [org.hibernate.tuple.entity.PojoEntityTuplizer],http://www.myexception.cn/eclipse/174629.html