How do I migrate an expired Mobile Me account to iCloud?

Question

I had a Mobile Me account which expired before iCloud was announced. I want to migrate this account to iCloud rather than signing up for a new iCloud account with a different email address. Is this possible? If so, how?

When I try to login at www.iCloud.com with my old Mobile Me ID I get the error below:

If I click 'Get Started' I'm redirected to www.me.com to login to my old account where I get the message below:

When I click on 'Learn More' I get directed to a support page which just says I can migrate from Mobile Me by visiting www.me.com/move but this just gives me the same result as above.

Has anyone managed to move an expired Mobile Me account to iCloud? If so, how did you do it?