February 2009 is a “perfect month”: it starts on Sunday, ends on Saturday.
It happened last in 1998; the next one will be in 2015.
Some people like to have their calendars start on Monday. That seems reasonable, since it keeps the two weekend days together, at the end of the week. Let’s call one of those perfect months a “second-order perfect month”. We had one in 1999; there’ll be another in 2010.