Group Streams: Untranslated strings showing front-end

I updated the avatar and cover picture of a group.. if I then click on the permalink of those stream entries I see untranslated strings:

1) APP_USER_PHOTOS_STREAM_UPDATED_GROUP_COVER_STREAM ( see it at mysite.com/ stream/item/27887 )

and

2) APP_USER_PHOTOS_STREAM_UPLOADED_GROUP_AVATAR_STREAM ( see it at mysite.com/ stream/item/27886 )

Thanks!