Yes. You need to add the accesskey attribute to the submit button of any form you want it to work with.
To see how it's done search the templates of a style in which it works for "accesskey", and you'll see which templates you'll have to edit and how to do it.
He has the accesskey attribute in place, the issue seems to be that Firefox requires the [SHIFT][ALT] key combo before the access character, whereas Chrome needs only the [ALT] key.