On CMSmatrix.org, some pending version tags cannot be displayed when an administrator tries to view the content.
I can reproduce the error by doing the following:
1. View my inbox on the site.
2. Click on the subject of an approve/deny email
3. The email provides me with a link to a new version tag to approve. I click it.
4. Now in the revisions screen, I see the content that is pending and I click on the view button.
5. I am presented with an error that says "The page you have requested does not exist. What would you like to do?" I have the option to add the missing page or go back to site.
When testing this, I created a regular user on CMSmatrix.org and then submitted news to the main CS on the home page. So, this news story was submitted correctly. I then logged into my admin account and attempted the steps above but could not view the pending submission.