I had a similar (?) problem some time ago.
http://forum.piriform.com/index.php?showtopic=18686
Finally found that these cookies were Chrome cookies left after I uninstalled Chrome. These cookies only appeared with CCleaner version 2.12 and later.
These Chrome cookies were in documents and settings\propri?taire\local settings\application data\google\chrome (something like that, don't remember exactly).
Since I've deleted any reference to Chrome no more problem.