Weeks between dates

If you consider 4/1/2011 to 4/7/2011 as one week, and 4/1/2011 to 4/8/2011 as 1w1d, then:

Int ( ( date2 – date1 + 1 ) / 7 ) & “w” & Mod ( date2 – date1 + 1; 7 ) & “d”