OPML Parser won't parse xml url's without an extension

I am working on a site that aggregates RSS feeds and thus wanted to use Feeds News / the OPML importer to import large swathes of feeds at once.

However, the OPML parser yields a "String could not be parsed as XML" error when I include RSS feed links in my OPML that are not explicitly labeled as .rss or .xml --- i.e. these are from sites like feedburner or just end in ".com/feed/". Is there any way Feeds / Feeds News' OPML Importer can parse these types of RSS feeds?

Here are a few examples:
http://www.fsrn.org/taxonomy/term/3/0/feed
http://globalvoicesonline.org/feed/
http://feeds.feedburner.com/CrisisGroupPodcast

Thanks for your support!