Redirecting from one TLD to another
Solution 1:
Try this:
<VirtualHost *:80>
ServerName example.org
ServerAlias *.example.org
RewriteEngine On
RewriteCond %{HTTP_HOST} ^(.*\.)?example\.org$
RewriteRule ^/(.*)$ http://%1example.com/$1 [R=301,L]
</VirtualHost>
..then have your other vhost (the one serving the content for example.com) configured with ServerName example.com
and ServerAlias *.example.com
.
Edit: made the matching of subdomains optional by adding the "?" quantifier