some problem with petclinic work

[moss]

I hava some problem with run the petclinic sample,the question is :
the petclinic wrok well when I don't change the item <param-value>/WEB-INF/applicationContext-jdbc.xml</param-value> to <param-value>/WEB-INF/applicationContext-hibernate.xml</param-value> in web.xml file.
the log of tomcat is:
org.springframework.beans.factory.BeanCreationExce ption: Error creating bean with name 'sessionFactory' defined in ServletContext resource [/WEB-INF/applicationContext-hibernate.xml]: Instantiation of bean failed; nested exception is java.lang.NoClassDefFoundError: javax/transaction/TransactionManager
java.lang.NoClassDefFoundError: javax/transaction/TransactionManager

I hava the jar that include javax.transaction.TransactionManager.class
my enviroment:tomcat5 + mysql5
Please help me!Thanks,I come from China.