Oops... KB 905872 only applies to IMAP accounts
The article "905872 You cannot limit the file size of the e-mail messages that you want to download in Outlook 2003" doesn't really mention in it that this only applies to IMAP accounts and not MAPI accounts. If you look at the registry key you get an idea that it applies to IMAP though. I submitted a change request to update the article.
