phoenix brand having no affect?

I've been branding things now, pk's, mobs, solo, in groups, and I see no change after I have branded something. The last group I was in, is a perfect example. One person using wrath, me using flame, and the other person just a iron weapon. Neither the wrath nor flame weapons had any affect on the damage being dealt after branded. I've tested it on arial prisoners, ugruks, and nightwalkers, with wrath, flame, and light weapons, no change. So to make a long story short, could you check it please?