Master Pages and Ajax UpdatePanel

[Guest]

hey all,
i have a page that's using a master page. it has 2 custom content
placeholders on it and was wondering if anyone has gotten an update panel
trigger to work accross the placeholders?
(i.e. i have a button in one placeholder and a textbox in another
placeholder and i'd like to add a trigger for the update panel for the
button's click event to write simple text in the textbox.

thanks,
rodchar