Changing the font size of the To, From, CC, Subject fields in Outl

I have configured my Outlook (2003) to have larger fonts due to an impairment
of my vision. I am able to configure all of the fonts for the menu's, title
bars, my text, when I receive emails - their text etc, but I cannot change
Outlook to display the To, From, CC, Subject fields in a larger font when I
receive emails.

It was possible in Outlook 2000, I cannot find it in Outlook 2003.

I've tried changing the font sizes in Windows, which upped the size of
everything again, but not the fields.