reuse CreateUserWizard as "EditUserWizard"

[Reinhard]

Hi,

I have a createUserWizard control on my page for unregistered users.

I would like to use the same page if registered users want to change
some of their data.

I am thinking of passing an argument (logged_in = true) to the page,
and based on this alter the behaviour of the Control to:
load User data into the text boxes.
on Submit: -> UPDATE instead of INSERT data

I know this is not supported out-of-the-box.

How can I do this? - subclass CreateUserWizard, or is there any
possibility to override or hook into the default methods of the
control?

thank you
Reinhard