by reading http://www.weston-fl.com/blog/?p=840, I noticed that on the required list of icons, there is one for settings as well, is it really needed?
Icon-settings.png 29 x 29 Universial application icon for settings area. Alternative name: Icon-Small.png
EDIT: found the article that details about the settings icon and setting bundle http://useyourloaf.com/blog/2010/5/18/adding-a-settings-bundle-to-an-iphone-app.html
If your app doesn't have an entry in Settings, there's no need for the icon.