Options on currency are not available at IB because they are not electonicaly trade, only trade in the pits.
I thought so too but found that currency options are available on Globex http://www.cme.com/dta/del/delayed_...uctFoiType=OOF&ProductVenue=G&ProductType=cur
If you are interested in trading Currency Futures OTC, at better spreads, commission-free, I've really liked CMC Forex (www.CMCforex.com) CMC is the oldest FX broker and has trading in the most FX products at the tightest spreads - all commission-free (Even the options)
My answer should be more specific: I have read about this fact that some currency option are available by electronic system, but they are not available when the pits are open, this is why IB don't attempt to trade them until the moment where we could have them available in anytime.
Options on Eurex futures are currently available through IB if you reside outside the United States of CFTC Restrictions. If you are a US resident you'll just have to play nice and be patient.