to duplicate your problem. Outlook is the default mail client for Word, and even setting Outlook Express as the default mail client did not change the Word default.
Does it work properly when sending a Word document as the email text rather than as an attachment?
The only thing I can think of at this time is that you do not have a valid account set up in Outlook, but do have one in Outlook Express. Word then might be forced to use the latter.
Hope this helps
Frank
When I try to send an Word document as an attachment, the software is trying to use Outlook express instead of Outlook 2003 which is my default.
The strange part is that this happens on only one of the two computers I have with Office 2003.
Ideas?
Thank you.

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