public static byte[] updateBuddyCapacity(int capacity) {
            MaplePacketLittleEndianWriter mplew = new MaplePacketLittleEndianWriter();

            mplew.writeShort(SendPacketOpcode.BUDDYLIST.getValue());
            mplew.write(21);
            mplew.write(capacity);

            return mplew.getPacket();
        }