Why can't I do a "with x as (...)" with ADODB and Oracle?

Ok, it really seems as though ADODB expects a query statement to actually start with select. Therefore, a work around for the problem might be to enclose the statement in a select * from ( .... ) like so:

Dim sql As String
sql = "with w as (select 'foo' x from dual) select x from w"

' enclose the statement:
sql = "select * from (" & sql & ")"

rs.Open sql, cn