Newbie seeks help on Photo Visual Confirmation Hack

I am looking at the code revisements that need to be made on the posting.php page, however I am not seeing the code in the page that I am suppose to be replacing or modifying. This includes anything referring to $confirm_code, get_code, etc. I am not sure if maybe I am missing something here, so I figured I would ask for clarification before messing up the board. If the code doesn't exist that I am to be looking for, am I to just add in the code from the hack. I am working with the original posting.php page. Any suggestions are appreciated.

I haven't had a chance to look at the last few phpBB 3 betas or gold yet. It could be that the confirmation code has been completely rewritten in one of those.

Apparently I have overlooked a major part of the equation. I installed this program via a hosting company offering. I could have sworn it said it was phpbb3, but upon looking at the main admin page, I see it is version 2.0.22. I guess that could answer a lot of issues I have had with this board. Sometimes the most simple things can make us feel like total idiots.