[2.0] DDC-381 - Unserialized Entity that was a proxy during serialize() will fatal when accessing methods that call _load() - A check for the existance of entity persister solves the problem.

[2.0] Fixed proxy classes to not invoke parent class constructors. We never call constructors to reconstitute persistent entities and proxies always represent persistent entities.

[2.0][DDC-237][DDC-216] Fixed. If you're using manual proxy generation through the CLI, please regenerate your proxies.

[2.0] DDC-194 - Fixed infinite recursion issue with references and @PostLoad annotation by telling proxy to be loaded before calling EntityPersister->load...

[2.0][DDC-49][DDC-50][DDC-33] Fixed DDC-49 and DDC-50. Also addressed DDC-33. Various other small changes and fixes. For problems with proxy objects please refer to the updated documentation.

[2.0] DBAL cleanups (DDC-46). Proxy class improvements (DDC-19, DDC-39). Started new UPGRADE_TO document for upgrade instructions between advancing Doctrine 2 versions.

[2.0] Accomodate joincolumn names in the metadata, in the selection and the hydration processes. Improved Api of the ProxyFactory. Working implementation of lazy loading for *-to-one associations (affects #2348)