9i: Nested table DML problem

We've just installed 9i on a Win2K server and have been playing around with it. One problem arose in some code we'd used to test the object features in 8i. The following code snippet, taken from a object type body, worked in 8i but does not compile in 9i:

 member procedure removeReference(groupID varchar2 := '', obj ref PObject := null)
 is
 begin
  if objectReferences is not null then
   delete from table(objectReferences) r    where (removeReference.groupID is null or r.groupID = removeReference.groupID)

   and (obj is null or r.objectRef = obj);

   if objectReferences.count = 0 then
    objectReferences := null;
   end if;
  end if;
 end;

"objectReferences" is an attribute of "this", the implicit object instance variable, and is a nested table type. Formally, the TABLE operator could take a local nested table variable as an argument; now the PL/SQL compiler complains with a "invalid table name" error.

Can anyone who knows better than I suggest a work-around (to be able to manipulate a local nested table using DELETE)?

TIA,
g

--
Gerard Averill
gaverill<at>chsra<dot>wisc<dot>edu