I have to admit that I couldn't believe my eyes :-)
After upgrading from EclipseLink 2.0.0 to 2.0.1, not only had the deployment NullPointerException gone, but the bytea to oid conversion seems to have been fixed too, without me having to specify the <type-converter> tag on all those classes i.e. just like in default Hibernate case.
Although all I had to do was swap out the persistence provider for the test, I couldn't help myself but physically remove the Hibernate jars just to certain I wasn't being fooled somehow...and sure enough, it all works just fine.
Well, I have to take my hat off to the Team!
Joe
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