Invite/Request Access--can't log in

I'm trying to get writer access to a friend's new private wiki. She invited me, and I got the e-mail with the link to the log-in page. I tried logging in with my e-mail and her wiki's password, no dice. I tried with my e-mail and my own wiki password, still no dice. So I requested access, and she tried to approve me but it is not working. The approve link just takes her back to the log-in page, which will not let me in! Help!
The wiki is http://periodicals.pbwiki.com
Thanks!