OLD INFO: I’ve solved this: http://www.hakoniemi.net/labs/scrollingOffset/nonbounce.html
NEW INFO: This is now a jQuery plugin that can be found from here: http://www.hakoniemi.net/labs/nonbounce/.
There are several issues, like losing the zooming capability when this is applied or it’s dynamic updating isn’t working fluently.
But now the simplest way is to define: <div class="nonbounce">...</div> and then $.nonbounce();