A cookie (DoubleClick) is made by Internet Explorer/Netscape and ONLY by Internet Explorer/Netscape. You cannot edit a cookie, and thus LimeWire's Uninstaller cannot either. Ad cookies are created almost every time you see an advertisement in a browser and are almost impossible to avoid. DoubleClick has an opt out cookie available on their site
here
It will not stop you from seeing their ads, but will stop them from keeping track of you. I don't think Ad-aware can tell the difference from the real and the opt-out cookie, so you must disregard the cookie in ad-aware the next time you see it, or they will resume keeping track of you.
-Dividend