The src code in the spring-security-core-2.0.4-sources.jar doesn't match with spring-security-core-2.0.4.jar (that has class files)

I am trying to run sample spring-security-samples-tutorial-2.0.4 war in a j2ee container in the debug mode. I found the class files like FilterChainProxy, ExceptionTranslationFilter, SpringSecurityFilter etc.. etc .. doesn't match with the src code present in spring-security-core-2.0.4-sources.jar. There is 1-2 lines difference between the class file and src code. It is sometimes frustrating to debug the code.

A fix with the correct version of source or class jar would help me significantly

Regards, Jagadish