There is no state that says it is illegal to have an baby in the front.
HOWEVER,
1) you will need to get an airbag-deactivation set-up, likely from the dealer
2) It is NOT RECOMMENDED for a REAR facing child seat to be near an airbag (but the deactivation kit should solve that concern)
3) This is all a bunch of hype by people who want to tell you how to run your life. Yes, the "safest" place for a baby is the "middle" seat of the "back" seat of a 15,000 lb behemouth, but only if you are on your cell phone
Point is, the goverment can't tell you what kind of car to buy (at least not yet). You think people in "texas" with 2 door bench seat pick-em ups sell them to get a "family car"? BS.
Keep the Boxster (heck, it is paid for). I also assume its not the only car in your home. if it is, well, then maybe you would need to sell so you can take wife AND kid AND you AND the stroller to the mall to keep buying more baby crap.
4) Do check local county and state rules. Most will tell you kids under a certain age/weight need to be in some kind of car seat, but that is all they should tell you.