I found a general bug on http://wordpress.org/extend/themes/
On the theme page there is a link to theme author profile.
When user name (author name) is the name of the domain, i.e. example.com
then link to the user profile on wordpress theme page looks like
http://wordpress.org/extend/themes/profile/example.com while should be
http://wordpress.org/extend/themes/profile/examplecom as the dot is not allowed to be in the url. It couses error 404 page right now, so hope it can be fixed soon.