I think that I might have found the solution, I am running Office 2003 and had the same issues, poking around my settings I have the Send\Receive settings also to automatic connect but would add any email to my Outbox.
The only way to send the email after typing was to hit F9 for Outlook to refresh.
Check out in Outlook - View - Status bar, should now be a small toolbar at the bottom of the window, lower right hand side there should be an Outlook icon with a down arrow beside it. If you click on that arrow a pop up box should allow you to deselect the Use Offline function, which will probably be checked.
I did that with my settings and now when I click send, the email is sent automatically.
Hope this helps.