Selecting email client to use with email merge

[sjmilldr]

I normally use Outlook as my email client and have it set up to read my
personal email accounts. On the side, I work with a non-profit group and need
use "email merge" to send out occasional mailings for them.

My plan was to use my Outlook Express for the non-profit mailings as I don't
use it for myself. So I set up the non-profit email account (POP3) to use
Outlook Express, temporarly set Outlook Express as my default emai client
under "Internet Options, Programs" and then ran a test email merge using Word
2002. The email did not go out when I opened Outlook Express but rather
waited until I opened Outlook.

So how does one tell Word 2002 (SP3) what email client to use when using
email merge?