It would be MY luck to get stopped and have the cop notice my cell phone was alcohol disabled and arrest me -- OWCH.
Kidding aside, no respectable drunk would subject him/her self to such limitations. You would have to make it mandatory by law on ALL cell phones and that would be a tough one to pass.
Possibly a better idea (and free) is to tell everyone that you have a "slurred speech and profanity detector" on YOUR cell phone which terminates the call on your end automatically and will NOT allow an incoming call from a previously terminated one for at least 8 hours. Of course, you need caller ID for this to work.
Hey!... someone should make and sell stickers for cell phones that say "profanity detect and terminate chip installed". Then, all you have to do is brag about (and show) your new feature to friends. The offender will learn quickly! hmmmmmmm
Keep thinking -- you're on the right track!