I'd never heard of it before, but according to wikipedia it's "highly astringent, though a jelly can be made from it." and (this would seem important) it has been used as an insect repellant. http://en.wikipedia.org/wiki/Callicarpa
I'd give it a taste & see what you think; if you think it's worth a shot, I say go for it! Should be easy to make a gallon of it just to see if it's worth it to make 6 gallons later.