iPhone 4 WIFI 11.n and Airport base station

[EagerDragon]

I am about to get 3 iPhone 4 and I have the 2009 Airport base station that allows me to run 2 networks, 1 in 5GHZ for 802.11N for new Intel Mackbooks at home and, 1 using 2.4GHZ for 802.11G for the 3 current iPhone 3G and 2 PowerBooks.

I was told that the new iPhone does 802.11n using the 2.4GHZ band, what changes do I need to make to the base-station if any to allow the following:
1) 802.11N for Intel MacBooks
2) 802.11N for new iPhone 4 (3 or them)
3) 802.11G for old PowerBooks

Any of you with similar environments please tell me what you did or are you running new iPhone in G band?

Thanks