Imported members before 3.0 - can they get blogs en masse?

Hey there, 2 part question:

I have about 4000 members on my site that I imported from ning. Is there a way to quickly give them the ability to have a blog?

Also, we had some spammers join and start a new blog, but then when we click the link to read their blog, it doesn't work, it goes to an error page. For instance, if you go to this page:

You can see two blogs (one is the spam "better life")

If you click it it takes you to and that is a page not found.