org.springframework.beans.factory.BeanCreationException:

严重: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory' defined in file [D:\java_tools\Apache Tomcat v6.0.29\apache-tomcat-6.0.29\webapps\dang_ssh\WEB-INF\classes\applicationContext-base.xml]: Invocation of init method failed; nested exception is org.hibernate.HibernateException: Hibernate Dialect must be explicitly set
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1338)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:473)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory$1.run(AbstractAutowireCapableBeanFactory.java:409)
at java.security.AccessController.doPrivileged(Native Method)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:380)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:264)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:261)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:185)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:164)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:423)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:728)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:380)
at org.springframework.web.context.ContextLoader.createWebApplicationContext(ContextLoader.java:255)
at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:199)
at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:45)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4135)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4630)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:791)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:771)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:546)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1041)
at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:964)
at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:502)
at org.apache.catalina.startup.HostConfig.check(HostConfig.java:1345)
at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:303)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)
at org.apache.catalina.core.ContainerBase.backgroundProcess(ContainerBase.java:1337)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1601)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1610)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(ContainerBase.java:1590)
at java.lang.Thread.run(Thread.java:619)
Caused by: org.hibernate.HibernateException: Hibernate Dialect must be explicitly set
at org.hibernate.dialect.DialectFactory.determineDialect(DialectFactory.java:57)
at org.hibernate.dialect.DialectFactory.buildDialect(DialectFactory.java:39)
at org.hibernate.cfg.SettingsFactory.determineDialect(SettingsFactory.java:426)
at org.hibernate.cfg.SettingsFactory.buildSettings(SettingsFactory.java:128)
at org.hibernate.cfg.Configuration.buildSettings(Configuration.java:2073)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1298)
at org.springframework.orm.hibernate3.LocalSessionFactoryBean.newSessionFactory(LocalSessionFactoryBean.java:814)
at org.springframework.orm.hibernate3.LocalSessionFactoryBean.buildSessionFactory(LocalSessionFactoryBean.java:732)
at org.springframework.orm.hibernate3.AbstractSessionFactoryBean.afterPropertiesSet(AbstractSessionFactoryBean.java:211)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1369)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1335)
... 31 more
2012-8-29 20:39:12 org.apache.catalina.core.StandardContext start
严重: Error listenerStart
2012-8-29 20:39:12 org.apache.catalina.core.StandardContext start
严重: Context [/dang_ssh] startup failed due to previous errors
2012-8-29 20:39:12 org.apache.catalina.core.ApplicationContext log
信息: Closing Spring root WebApplicationContext
2012-8-29 20:39:12 org.apache.catalina.loader.WebappClassLoader clearReferencesJdbc
严重: The web application [/dang_ssh] registered the JBDC driver [com.mysql.jdbc.Driver] but failed to unregister it when the web application was stopped. To prevent a memory leak, the JDBC Driver has been forcibly unregistered.
2012-8-29 20:39:12 org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
严重: The web application [/dang_ssh] appears to have started a thread named [Timer-0] but has failed to stop it. This is very likely to create a memory leak.
2012-8-29 20:39:12 org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
严重: The web application [/dang_ssh] appears to have started a thread named [MySQL Statement Cancellation Timer] but has failed to stop it. This is very likely to create a memory leak.哪位高手知道这是啥错误?