Just tried it out...

It doesn't seem to be working for me on 3.7.

To be sure I'm understanding correctly, I should be able to install this, log in to my forum on the .com domain, then go to my .net domain and still be logged into the forum browsing the forum on .net, right? When I go to .net I'm not logged in.

You did make the template edit and upload the file to both includes directories and add both domains to the new vB setting?

Yeah I did all that, though I guess one part I don't understand is "upload the file to both includes directories". Both domains access the same site. All the same files and database, just can be accessed with multiple domains.

Okay - what value have you entered into the setting?

First I used

neverboredonline.com
neverboredonline.net

When that didn't do anything I put in

neverboredonline.com/forum
neverboredonline.net/forum

That didn't do anything either. Each time I would clear the cookies, and do a fresh log in via .com. Then I would go to the site via .net and I'm not logged in.

Okay I think the issue is that your forum is located at /forum.
So you would have to use the /forum version.
Also make sure to start each entry with a .
I think you might be getting 404 errors without it.

Awesome man, thanks. It's working now. I wasn't even seeing the instructions to add the . at the start of the entries even though I read through it multiple times, lol. Thanks

Actually, I'm having some problems still.

First problem, it's not working in IE 7. (It's working in Firefox)

Second problem, when a user logs out it completely clears the who's online list.

Thanks for the report. I'll look into this.

Okay, I figured out why the Who's online list was getting cleared, but the fact that this isn't working in Internet Explorer has me stumped. It's as if Internet Explorer is reporting the originating domain to the script rather than the domain the script is actually running from... If anyone has any ideas please let me know, because I hate IE.