I'm not sure that having the exact wavelength is all that much of a problem. But I am worried that, while it may be possible to send CIR signals using IrDA hardware (by "slowing down" the on/off pulses in one manner or another), it could be much harder to go the other way; does hardware exist that can drive a CIR-style LED at the speeds needed for IrDA? Will the output of a CIR-power LED oversaturate the IrDA receiver? (I'm kind of guessing that the IrDA power levels are as low as they are in order to avoid this kind of oversaturation problem; otherwise, nobody would have ever created an interface that forced you to place two devices a few centimeters apart in order to function properly.) Also, could an IrDA rx be able to read signals from a wide range of existing CIR remote controls? (If not, use as a "learning remote" becomes impossible.)

I do agree that having both a powerful CIR signal along with the ability to communicate over IrDA all in one package would be nirvana. I also believe that if it were that easy, someone would have already done it twenty years ago when IrDA was designed; it would have made adoption of the technology much quicker (and I'd suspect that it would still be popular today).

In any case, please do test the hardware chosen for the Neo900 before you finalize it!