Supported EMF Features
The current version of the EMF - JPOX integration supports the following EMF Features:

All relevant primitive types (including Date)

Lists of primitive types (EDataTypeEList)

Single Reference: contained, non-contained, one-way, two-way

One-To-Many relations (EList): contained, non-contained, one-way, two-way

Many-to-Many relations (EList): contained and non-contained, one-way, two-way

Notifications and adapters (limited testing done)

Enumerations

Resource implementations

Lazy loading (similar to EMF proxy feature)

Dynamic api

Inheritance between types

No dependencies on EObjectImpl as root object or specific root object for persistency: EMF Objects are only required to implement org.eclipse.emf.ecore.InternalEObject

Support for EMF Feature Map as described here