刚接触java，用netbeans做了个小程序，数据库是mssql2k
做好后在netbeans中打成jar包就出现了问题
没打包之前在运行没有问题
打包后jar包不运行
程序运行也报错：
Exception in thread "AWT-EventQueue-0" javax.persistence.PersistenceException: No Persistence provider for EntityManager named localhost:1433;DatabaseName=teacherloadPU: Provider named oracle.toplink.essentials.PersistenceProvider threw unexpected exception at create EntityManagerFactory:
oracle.toplink.essentials.exceptions.PersistenceUnitLoadingException
Local Exception Stack:
Exception [TOPLINK-30005] (Oracle TopLink Essentials - 2.0.1 (Build b09d-fcs (12/06/2007))): oracle.toplink.essentials.exceptions.PersistenceUnitLoadingException
Exception Description: An exception was thrown while searching for persistence archives with ClassLoader: sun.misc.Launcher$AppClassLoader@19821f
MANIFEST文件里的Class-Path，格式路径都完整
请帮忙各位解决
------解决方案--------------------
连接数据库的问题。
oracle.toplink.essentials.exceptions.PersistenceUnitLoadingException
这行有oracle不知是干什么的，你用的是微软的sql server吧？
------解决方案--------------------
外部的jar没有在classpath里面吧