Showing Two Calendar Months in the Navigation Pane

How can I customize Microsoft Office Outlook 2003's navigation pane to show two calendar months on the left when I view my Calendar folder?

By default, the navigation pane shows a thumbnail calendar for just one month at the top, above the My Calendars list. But there are at least three ways to have Outlook show more thumbnail calendars:

Unfortunately, you still can't make Outlook show thumbnails for last month and next month. Instead, it always shows the month that's currently displayed and the next months after that one.