Yes on P2P thats simple:
NPC Code:
addguildmember account,nickname,guild;
removeguildmember account,guild;
i think thats the right syntax, i'll have to check, i'll check later...
but its only p2p, its managed with npcserver.
also, there is some thing you can do to make it add forever, i'll look when i get home, i hqave it somewhere... :-P