Image itself is included with User.gwt.xml and the only deferred binding that Image uses can be found in ClippedImage.gwt.xml (defines special behavior for IE6, and is also included via User.gwt.xml). So GWT.create(Image.class) should just work.
Maybe its just a cache issue? Clean the gwt-UnitCache folder and the browsers cache and reload the page. If this does not help, increase the log level of dev mode to Trace/Debug and see what the deferred binding logs tell you when using < IE9
-- J.