On a site I run, we have a relatively self-policing, open (but spam-filtered) commenting community - which includes allowing users to enter a free-text nickname and email address.
Unfortunately, we occasionally have one minor troll who insists on pretending to be another member who he doesn't like. Doubly unfortunately, its' a situation where a simple IP ban isn't going to work.
It's low level annoying behaviour, so what I'd quite like to do is add some kind of function that:
1) Triggers when a new comment is added
2) Checks whether the "name" field is a certain value, and if so what "email" was entered
3) If the email isn't the actual members address, marks the comment for moderation so it doesn't insta-appear.
I'm familiar with PHP and from googling realise that this probably involves adding a hook in the functions.php in my theme, I'm just a bit confused beyond that - which is annoying as it feels like this is probably something very simple if you know what you're doing!
Any help would be appreciated...