 the address of the procedure
       is used as a lookup key to identify the associated instance data.
      </P
><DIV
CLASS="CAUTION"
><P
></P
><TABLE
CLASS="CAUTION"
BORDER="1"
WIDTH="90%"
><TR
><TD
ALIGN="CENTER"
><B
>Caution</B
></TD
></TR
><TR
><TD
ALIGN="LEFT"
><P
>        On Windows, functions can have two different addresses: one visible
        from outside a DLL and another visible from inside the DLL.  One
        should be careful that only one of these addresses is used with
        <SPAN
CLASS