How about this; still a little kludgy, but it works
Code:
function getNumberSuffix(dNum)
{
daySuffix = 'th';
if(dNum != 11 && dNum != 12 && dNum != 13)
{
if(dNum > 9) { dNum = dNum % 10; }
if (dNum == 1) { daySuffix = 'st'; }
if (dNum == 2) { daySuffix = 'nd'; }
if (dNum == 3) { daySuffix = 'rd'; }
}
return daySuffix;
}
So you just call it like getNumberSuffix(14)