extended objects with read_property and get_property_ptr_ptr

I was playing around with Bug #28817 and seem to have run into an issue when overriding the read_property handler with an extended object (this case a DomDocument object). In order to support standard properties correctly, such as $obj->myprop['a'] = 'b', the internal object needs to support get_property_ptr_ptr. As the internal object here overrides the read_property handler, it would also need to override the get_property_ptr_ptr handler to make that standard property work correctly, which is where I have run into some problems. At first, I implemented a get_property_ptr_ptr handler, but found that for the base internal class properties, this method needs to return NULL so that cases like zend_pre_incdec_property would fall back to the read_property/write_property handling. Next was to return NULL for all properties of the base internal class and return the result of the standard get_property_ptr_ptr for non base class properties. This fixed the standard properties, but returning NULL for the internal base properties breaks calls like: $document->documentElement->ownerDocument; because zend_fetch_property_address_inner will not fall back to the read_property handler if NULL is returned get_property_ptr_ptr. Rather the error "Cannot access undefined property for object with overloaded property access" is returned. Is this is a pitfall of the engine or is there something I am overlooking which would allow this to work across all cases? Thanks, Rob