I recently asked a tax advisor a similar question: if I do a cashless exercise sale for $5 when the FMV is $6 and my strike price is $2, can I pay income tax only on the $5 sale price? The answer was no: I would owe income at the $6 price and then immediately accrue capital losses on the $1 spread between sale and FMV.

I guess that's a longwinded way of saying "I doubt it". Tax law around employee options is brutal. :/