Office 2003, Win XP Pro SP2, English-US

In a macro (created by the Record facility) I have

Selection.Sort Key1:=Range("E2"), Order1:=xlAscending _
, Key2:=Range("D2"), Order2:=xlAscending _
, Key3:=Range("F2"), Order3:=xlAscending _
, Header:=xlYes, OrderCustom:=1, MatchCase:=False _
, Orientation:=xlTopToBottom

What column E contains is either a letter M, a letter S, or a blank.
I want the sort to put all rows with the blank first (using keys 2
and 3 as tiebreaker) and then all rows with the nonblank (regardless
whether it's M or S). In other words, in column E I want letters M
and S to rank equally in the sort of column E, but columns D and F
will be sorted by the normal alphabet. If possible, I want to do this
right in the sort statement.

I know I could do this by creating a dummy column J. Every cell of J
could contain =isblank(E2), =isblank(E3), etc. But that's cumbersome,
and it requires me to remember to extend formulas in J whenever I add
a row in the middle of the table, which I do fairly often.

Is there a way to put some expression as a sort key to accomplish
what I want? I spent some time with the help and couldn't find
anything useful.

--
Stan Brown, Oak Road Systems, Tompkins County, New York, USA
http://OakRoadSystems.com/