posts suddenly not displaying properly

I created a new post on my site and suddenly it does not display properly. The “rightcol” div is displaying inside the “centercol” div. Previous posts still look fine. If I view source in my browser I think can see the offending code:

“<!–/box –>
<!– </div>
<!–/centercol –>

The </div> for centercol is getting commented out. It has been more then a month since I posted anything on the site and I may have customized something in the theme files since then, but I can not find where this offending code is coming from. I am not a programmer, just know enough to be dangerous I guess, and I do not know how the code gets generated for these posts. Here is an example:

good post: http://getpaidfishing.com/dellavalle-and-hawley-win-gold-medal-with-olympian-effort-at-friday-paycheck-tournament-6-august-3/

bad post: http://getpaidfishing.com/piccolo-and-pops-steiner-win-final-paycheck-friday-tournament/

Any help is greatly appreciated – Thanks! bryan