A lot of the original ipod port of Rockbox was done by looking at how the iPL folks had done stuff - so yes this is possible.
BUT :
1) Their driver only works on 1st, 2nd and 3rd Gen iPods. This means it won't work on B&W 4th Gens, Colour 4th Gens (iPod Color), 5th Gen, 5.5th Gen, either Mini, any Nano, and, should work on the Classic and Touch start eventually, it won't work on them either. That means it's a VERY narrow Rockbox target band you're aiming it. Which is why :
2) No-one has done it - because it's a fraction of Rockbox targets, and we TRY to keep the experience the same across all our targets.