allowable specializers

[goldman@vaxa.isi.edu]

Re: Gregor's note on allowable specializers:
    The only permissible parameter
    specializers are classes and lists of the form (EQL <object>).
I presume that "classes" here encompasses types defined by DEFSTRUCT
(without the :type option)?

The way I read "Integrating Types and Classes" in chapter 1, I would expect
(portably) to be able to use the name of a defstruct type as a specializer
in the same places where I could use the name of a class introduced
with defclass.  Is that correct?  Is there any way to use defstruct types
as specializers in PCL (without defining a new kind of generic function)?

Neil