The RSS image is on the wrong element.

The RSS image is in the menu background. It could be moved to the background of an inline div surrounding the RSS link so the image will stays with the link when the menu runs over one line or the width is changed. http://d-theme.com/dark_elegance has two lines of menu. The RSS link is at the end of the second line and the image is at the end of the first line.

Running the black background of the menu to a second line is not a problem. It is done in some other themes. See http://drupal.org/node/343829#comment-1293392 for the equivalent change in Dreamy.