Question about a dixi template

On the footer of my theme, I have this error
"Error Processing Feed: Use of undefined constant BP_ROOT_BLOG - assumed 'BP_ROOT_BLOG' at /services/webpages/c/a/calzone.org/public/tld/wp-content/themes/wpmu-dixi/functions.php line 212"

You can see the error on the subdirectories at calzone.org/tld/

How do I fix this?

Thanks