Comments allowing multiple email addresses

Hi,

My website (https://chiefscommand.com) is allowing comments from email address which are registered to a user.

I’m not sure when this happened, but I noticed the other day that a regular user made a comment, but his profile pic was not included.

I checked to make sure the comment was made with the email address on his registered account, and it was. I have since went into the database and changed the user ID of the comment to match that of his profile… but what a pain in the ass.

My website is a NFL blog, so it didn’t get much attention in the offseason. Before the start of the 2011 season I updated WordPress from 2.X to WordPress 3. I also updated the theme from a hacked up Marketplace to a hacked up Avenue.

I am almost positive that a registered email address could not be used for a non-logged in comment previously, but I have looked everywhere and cannot find the solution.

Any guidance would be greatly appreciated.

Thanks!