defclass options

[Billy Joel <riedesel@daneel.den.mmc.com>]

I'm a bit confused.
In the defclass definition in the SIGPLAN notices (as well as CLTL2ed)
there are three clas options: :default-initargs, :documentation and
:metaclass.
However, I have also been using :accessor-prefix in my classes.
This lets me basically use the accessor-prefix for all the slots in my
class for both reading and writing instead of having to go and
set :reader and :writer on each slot.

Is this a non-supported option I am using or what?  (Maybe I am missing
something in the document I am reading...)

Thanks,
Joel