The reason I mention warranty is because in the US, most emisions related problems are normally only covered for 4 yrs/50K miles by federal law. There are now some items covered longer on some newer cars but for the most part, it's still 4/50 and after that, most auto manufacturers do not pay the dealer or car owner for anything that occurs causing the car to fail emisions.
Appartently in your case, they've made an exception but from what I've seen so far, that's not the norm with this situation.
The times I've seen where cars ran into this was after an emissions related part was replaced (check engine light came on) and adaptation was reset. The car then needs to go through a process called a drive cycle and this can take time normally. Under most circumstances, the car does this by itself while the customer's driving the car and there's no problems. Other times, the car possibly previously failed an emissions test so after repairs were made, the car then heads back to the testing station yet it's not been long enough for it to normally complete this drive cycle and it's that that's now being picked up by the states equipment.
If the above senerio fits your cars description, then there's probably nothing more really wrong with your car even though the state's telling you otherwise.
Like I said earlier, if your car can pass the old test of sampling exhaust and no FAULT codes exist, then IMO it's the state (not Volvo) who's being rediculous about this. I hope that Volvo and these state testing people can resolve this bad situation as it's presently not fair to anyone trying to deal with it as is. I'd have to also think that Volvo's probably not the only car manufacturer with this newer state emissions testing proceedure problem.

Please keep us informed (here, this board) as I too want to know how this bad situation will ever be finally resolved.