Use bogo_get_post_locale() instead of get_post_meta(). There are cases where a post doesn’t have a particular _locale meta record (such as posts that have created before installing Bogo). bogo_get_post_locale() can use the default locale as a fallback.

git-svn-id: https://plugins.svn.wordpress.org/bogo/trunk@1035903 b8457f37-d9ea-0310-8a92-e5e31aec5664