Blog Directory plugin's search is not working when wpmu in subdirectory

Blog Directory plugins, its search is not working correctly if you have wpmu installed in a subdirectory. Instead of return search results, the search points to an error page (page not found) with URL of http://mydomain.tld/blogs/search/, ain't it supposed to point to http://mydomain.tld/wpmu/blogs/search/? How to fix this?