I don’t think so because for the time being the iPad cannot interoperate with the Onkyo ND-S1 iPod/iPhone dock:
http://www.soundmancaraudio.com/home/2010/4/11/first-ipad-in-a-car-part-2.html
The Apple IAP authentication procedure is something like the following:
Apple authentication chip of the Onkyo ND-S1 -> iPad:
Hi! I’m an iPod/iPhone authenticated auxiliary device. Could you please open your digital audio gate?
iPad -> Apple authentication chip of the Onkyo ND-S1:
No! I can only open my digital audio gate if you are an iPad-authenticated auxiliary device
However, if Apple people don’t want to get shot in their foot (by Android devices), the Apple authentication procedure in the upcoming Apple firmware could be the following:
Apple authentication chip of the Onkyo ND-S1 -> iPad:
Hi! I’m an iPod/iPhone authenticated auxiliary device. Could you please open your digital audio gate?
iPad -> Apple authentication chip of the Onkyo ND-S1:
Yes! I can open my digital audio gate, because you are either an iPad-authenticated auxiliary device or an iPod/iPhone authenticated auxiliary device.
or
Apple authentication chip of the iPad camera connection kit -> iPod/iPhone:
Hi! I’m an iPad-authenticated auxiliary device. Could you please open your digital audio gate?
iPod/iPhone -> Apple authentication chip of the iPad camera connection kit:
Yes! I can open my digital audio gate, because you are an iPod/iPhone authenticated auxiliary device or an iPad-authenticated auxiliary device.