It now includes players with a British passport whose only tie to a country is attending school there for five years. Smith will now hope that Driver will choose Scotland over England.
The 21-year-old Hearts winger will now be considered by Scotland manager George Burley for next month's friendly against Wales in Cardiff - but only if he intimates that he would be happy to switch from England.
Driver was born in Oldham but raised in Scotland and represented his country of residence at schoolboy level. He had previously said he would be delighted to play for Scotland but also expressed his pride at being capped by the England Under-21 side for the first time earlier this year.
Smith first gained agreement for the rule change from Northern Ireland, Wales and then England. Following Saturday's friendly defeat by Japan, Smith confirmed that this had been approved by Fifa's committee last week.
Driver was wanted by Burnley and other English clubs, but no move was concluded before the closure of the last transfer window.