Inner Class Entities

[Tim McConnell]

Hi, I'm wondering if there is any documentation, specifications, and/or known 
rules that govern the usage of Inner Classes as Entities ?? I haven't been able 
to find any although I do see  a couple of examples of the @Entity being used on 
inner classes in some of the OpenJPA testcases. Unfortunately, those examples are 
not quite enough for me to fully understand the restrictions or implications. 
Thanks for any additional information...
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Thanks,
Tim McConnell