I have tested Cookie Pal with K-Meleon and it worked all right. (You have to replace Mozilla path with that of K-Meleon.)
But CookiePal is shareware, so I decided that it would probably be less trouble to write a macro for PFE (or any other text editor) to open cookies.txt and to put that macro in the Edit menu of K-Meleon (if I ever wanted to edit my cookies). When I had all the cookies I really needed and I had cleaned out the cookies I did not want, I made the file cookies.txt read-only. That disables the addition of any unwanted cookies, lets K-Meleon use the necessary cookies, and sites requiring cookies always let me in.
There is also a thread about that at
http://kmeleonbrowser.org/forum/read.php?f=1&i=2377&t=2349