Which admin was it? Did you talk to him? Explain that you had a weapon out and were you engaged in battle?
Were you hiding/far from the action? If you are trying to flank or something, say so, make it clear that you just play a naked build and are still contributing to the game, and not trying to leech. AFAIK nudity is allowed on all servers as long as you are in the fight and not leeching.
Anyway, as a Spartan you should be at least wearing a Barbutte helm, some sort of boots, and holding a spear, sword and shield. That should be visual enough to indicate that you are not leeching, just choosing to use different gear.
