seam generate entities出错,该怎么解决

seam generate entities出错
我用JBOSS SEAM TOOLS+ECLIPSE3.4生成一个SEAM WEB PROJECT(WAR),然后点击new->seam generate entities通过数据表生成实体BEAN时出现以下提示,敬请高人解析.
提示:MS SQL SERVER JDBC已正确安装并且SEAM WEB PROJECT的数据源配置是正确的.

Can't generate seam entities
  org.hibernate.console.HibernateConsoleRuntimeException: Problems while loading database driverclass (com.microsoft.jdbc.sqlserver.SQLServerDriver)
  Problems while loading database driverclass (com.microsoft.jdbc.sqlserver.SQLServerDriver)
  org.hibernate.console.HibernateConsoleRuntimeException: Problems while loading database driverclass (com.microsoft.jdbc.sqlserver.SQLServerDriver)
  Problems while loading database driverclass (com.microsoft.jdbc.sqlserver.SQLServerDriver)
  java.lang.ClassNotFoundException: com.microsoft.jdbc.sqlserver.SQLServerDriver
  com.microsoft.jdbc.sqlserver.SQLServerDriver


------解决方案--------------------
MSSQLJAR包都导入看看。