Username and password on another forum

[~DS~]

I just created a demo site for testing and I was wonder if it's possible to have the same username and password from my current forum like Multi Forum Mod but instead I choose which members can access so they don't need to sign up and register again.

[Kindred]

is the first forum on the same server?

You can turn on OpenID registration which would allow them to share their OpenID account across sites, and then turn on the Admin approval required for membership in order to keep out the riff raff.

[~DS~]

I get a error: "The requested identifier did not return the proper information."
Want to clarify what I mean, let's say this way:

This is regular member

mysite.com  username: Shadow, password: 12345

mydemosite.com  username: Shadow, password: 12345

They are hosted under the same server but different domain.

Same or Shared account, which mean they don't have to register again, just enter the username and password. I know it can be done via Open ID or the database but I dont know how.