i don't know i would be careful using Febreeze though. i have always felt that it puts a ....."film?" (not sure what word i am looking for here)...on the fabric after it has been used. just never feels clean to me i guess. the sweet smell of febreeze always makes me slightly naseous too so there is that to consider as well.
as much of a PITA as it could be, i would say that if sitting out in the sun doesn't help it then i think Silver's suggestion would be the best one. that way you get it clean without any sort of shtuff on it.