exec procname(p1, ..., pn)
 
or
 
begin
  procname(p1, ..., pn);
end;
/

sql>create or replace type myNumberTable is table of number;
  2  /
 
Type created.
 
sql>create or replace function f_get_number_table_from_string(
  2    p_string     in  varchar2,
  3    p_delimiter  in  varchar2 default ',')
  4    return mynumbertable
  5  is
  6    v_string  long := p_string || p_delimiter;
  7    v_pos     pls_integer;
  8    v_data    mynumbertable := mynumbertable();
  9  begin
 10    loop
 11      v_pos := instr(v_string, p_delimiter);
 12      exit when (nvl(v_pos, 0) = 0);
 13      v_data.extend;
 14      v_data(v_data.count) := trim(substr(v_string, 1, v_pos - 1));
 15      v_string := substr(v_string, v_pos + 1);
 16    end loop;
 17    return (v_data);
 18  end f_get_number_table_from_string;
 19  /
 
Function created.
 
sql>create or replace procedure myproc( 
  2    p_list_id in varchar2 default null,
  3    p_recordset out sys_refcursor)  -- this is 9i only, your cursor type is fine in 8i
  4  is
  5  begin
  6    open p_recordset for 
  7      select object_id, object_name
  8        from user_objects
  9        where object_id in (select *
 10                              from table(cast(f_get_number_table_from_string(p_list_id) as myNumb
erTable)));
 11  end;
 12  /
 
Procedure created.
 
sql>var rc refcursor
sql>exec myproc('30136,31510,30140', :rc)
 
PL/SQL procedure successfully completed.
 
sql>print rc
 
OBJECT_ID
---------
OBJECT_NAME
------------------------------------------------------------------------------
    30136
MYNUMBERTABLE
    30140
F_GET_NUMBER_TABLE_FROM_STRING
    31510
MYPROC
 
3 rows selected.