Upgrading from Office 2003 Small Bus to Office 2003 Pro

I recently upgraded to the Office 2003 Professional version from the Small
Business edition. But the XML features of the Pro version do not appear to
be available to me in Excel. In fact, in the "About Microsoft Excel" screen,
it still appears to be using the Small Business Edition.

Originally, before upgrading to the Small Business Edition, I had Microsoft
Works, which should make me eligible for the upgrade. Do I need to uninstall
Small Business Edition before installing Pro in order to get the full benefit
of the Professional version? And is there any way to do that without the
Small Business CD?

Thanks for your help,
Kelly