Thanks for your efforts, but we can't use an image so closely derived from a copyrighted work. It has to be original art, public domain, or licensed in a "free" manner (GPL-compatible).
Also, I suppose it's not for me to say, but I'm under the impression that the rabbit is an informal mascot based on an inside joke, not the official icon of aMule. Of course, I don't know that there is an official icon.