Spring 3.1 Hibernate 4继承异常[无法强制转换为org.hibernate.mapping.RootClass]

Hi I have just started using Spring , with Hibernate4 and maven. Basically my class hierarchy is HUmanMicroTask extends from MicroTask . In future there may be several other classes extending from MicroTask. I was trying to have a one table per concrete class which is the simplest way to get up and running with spring3 and hibernate 4. However when i run my code. I keep getting the following exceptionHi I have just started using Spring , with Hibe