I poked around a bit and found http://wiki.dreamwidth.net/wiki/index.php/Wiki_Tasklist#Bureaucrat_Tasks. That allows granting rights through group membership, and I'm pretty sure it works (or at least used to work) for OpenID accounts as well, since that's what my account was at first (it's a full account now). But if it doesn't, https://www.mediawiki.org/wiki/Manual:Account_creation hints that http://wiki.dreamwidth.net/wiki/index.php/Special:CreateAccount should let an administrator create an account for another user.

suggesting that you post information of interest to developers

Which "you" is that, me or nataraj?