Named Parameters

Apparently this is "fixed" in 11g, but the question is - why wasn't it supported in the very first place ?

SQL> create or replace
  2  function f( x number) return number is
  3  begin
  4    return 1;
  5  end;
  6  /

Function created.

SQL> select f(1) from dual;


SQL> select f(x=>1) from dual;
select f(x=>1) from dual
ERROR at line 1:
ORA-00907: missing right parenthesis