Vintage heads still in production? Are vintage Lego heads with the classic grin still in production?

I am having trouble deciding whether the head-with-grin piece (element ID 9336, called "MINI HEAD NO.1") which is produced today (and available in the Bricks and Pieces online store) is 100% identical to the classic head used in the 70s, 80s and 90s. If not, what's the difference? 



Visually I think it looks the same, but it appears that 9336 is not the code used for vintage sets.
Yes, visually the simple smileys are the same now as in the past. The difference is in the stud. Some have a stud like what you have pictured above; with an open stud and others have a solid stud. Other than that, the face itself is exactly the same. You can three all three versions of the stud here (solid, recessed open and recessed blocked) here:  http://www.bricklink.com/catalogList.asp?pg=1&amp;q=standard+grin+pattern&amp;catLike=W&amp;v=2