I'm not sure if it's possible and ca,'t try it now, but : maybe you can access to geometryLibrary: var geom :GeometryLibrary = yourObject.geometryLibrary you can acess geometryData from there: geom.getGeometry(name).minX, geom.getGeometry(name).maxX, etc...
but the fact is I don't know what the name should refer (try name of your Object). Well sorry this won't help much... ;-)
