[Plugin: WordPress Importer] Importing attachements?

I have imported a site from posterous into wordpress.com.

That has worked quite well appart from the fact that all the attachements are still linked from my old posterous site.

So when I export my wordpress.com site to an xml file and then re import it into a hosted wordpress site, I get the same linked media.

Is there a way to import all the attachements onto my host ?
I tried the plugin “add linked images to gallery” but that didn’t work at all.

Is there any other way to do this ?

I really would like to get all my media off of posterous.

Thanks.

https://www.ads-software.com/extend/plugins/wordpress-importer/