Futures, including single stock futures are OK to trade on IRA. Please, do not confuse margin and performance bond requirements.
From http://www.interactivebrokers.com/en/general/education/faqs/ira.php
What can I Invest in?
Stocks, covered call writing (covered shares are restricted), buying calls (funds equal to the aggregate exercise value of the long calls are restricted), and buying puts (shares subject to exercise are restricted), selling cash secured puts, spreads securities with European style expiration, futures contracts, and futures options. The IB IRA is structured as a Stock Cash Account (if you choose to trade only stocks) or as a Stock Options Level I Account (if you choose to trade options in your IRA). IRAs may also invest in US dollar denominated futures contracts, and future option contracts.
1. There is no such thing as margin IRA. It does not mean that futures are prohibited. Futures do not require margin. There are only performance bond requirements in this world.
2. Whatever is called sometimes "margin IRA" in IB has just a benefit of fast settlement of stock trades. Nobody is capable to borrow money.