Allow CC and BCC columns in Inbox

With Single Line mode on and conversations off (or in detail only), it's possible to show the To column in Inboxes. This is very useful for us, as we use a separate application to send out large numbers of emails to clients, and copy ourselves in so we can see that they've been sent and have a record of them. Adding the To field as a column means we can see the 'main' person the email was sent to, but we can't show the CC or BCC columns - please can these be made available as well, for the same reasons - it's very helpful when there are lots (80,000+ / week) and we need to check them! Many thanks.