When is today not today? When the month started on a weekend (as August 2004 did) and you either you use the compressed weekend view or have the calendar set to begin the week on Monday. The last week of the previous month will be shown at the top of the screen, ending with the first day or two of this month at the end of the week. The last week is off the bottom of the screen because Outlook only displays 5 weeks. Because 'today' is in the last week, it's not shown unless you press the today button or scroll down.

This isn't a bug, its expected behavior (or "by design") because of how Outlook displays weeks and your choices are:

1. Disable Compressed weekends. (r-click on the calendar, choose Other settings) or change the month to begin on Sunday.
2. Press the today button (or r-click on the calendar and choose Today)
3. Wait a couple of days - when the next month moves to the top of the calendar, the problem is solved until the next month that begins on a weekend. :)

For an explanation and screenshots illustrating the issue, see Help! Outlook displays the end of last month, not Today.