Critical show stopper bug with Liferay 6.0.6 Ext plugin (SDK PLugin based)

[12年前 に Sarav Veda によって更新されました。]

I have added few methods in *LocalServiceImpl and executed the service builder to generate the methods in Util class, but after deploying the Ext war file it prompts me to restart the server, on server restart- application deployment it throws spring bean intialization exception and the root cause is:

Throwing Duplicate Mapping error,
Caused By: org.hibernate.DuplicateMappingException: Duplicate class/entity mapping com.liferay.portlet.documentlibrary.model.impl.DLFileEntryImpl

I believe over riding the liferay source file in extension is very basic functionality but in 6.0.6 GA version, even we do have error in this.
For more info: http://issues.liferay.com/browse/LPS-18176

Thanks