Comparing system date with oracle date

Does anyone know how to compare the current system date in php with an oracle date? I have logic such as:
if(date("d-M-y") > $results["DATEDUE"][$i]){
print('Item is late');
}
else
{
print('Item is NOT late');
}
If the current date is larger than datedue, it should enter the if statement and print out a late notice. If the current date is the same or ealier than the datedue, it should enter the else clause. Unfortunately, when the dates are identical, the program enters the if--saying the item is late.

What am I doing wrong here?