Splash screens and progress dialogs

Hello
    With an application (small) now up and running I'm in prettification
mode. What I've been searching through the CAPI docs for is some sort of
dialog or similar that would allow behaviour such as;

(do-with-dialog :title "A title"
                :message "Calculating x y and z"
                :function #'my-function
                :args '(1 2 3 4))

Pop up a dialog, without close/minimise buttons and go away as the
function returns. I've seen something similar in other non-lisp
libraries. So, my question is, is there a component I've missed or an
easy way to do this with the components CAPI provides. I've had a look
at creating a dialog but soon get lost in how to trigger the function,
callbacks etc.
    On a related note, something similar to give a splash screen effect
would also be handy.

        thanks

                Andrew

-- 

Andrew Lawson
adl@absentis.com
http://www.absentis.com