[development] Feed Aggregator xml Errors!

Hello, I have been experiencing some problems with Feed aggregator in Drupal 6.8 When I run cron manually, it shows me the following errors: The feed from National Geographic seems to be broken, because of error "Invalid document end" on line 15.The feed from National Geographic seems to be broken, because of error "200 feed not parseable". I am using openSUSE 11.0 can anyone help?!?! Thanks, Radhika