How to obtain the document interface thru MSAA for Opera?

Hi,

maybe somebody knows how to obtain a DOM-like interface thru MSAA for Opera 
browser.

For example, Mozilla browser provides a set of ISimpleDOM... COM-interfaces, 
which can be

obtained thru Microsoft Accessibility mechanism and used to analyze the 
document structure.

In other words, how to get an access to Opera's DOM interfaces from external 
program under MS Windows?

Is there a good internet resource for this kind of discussions?

I'll be appreciate for any help,

Boris