sorry to resurrect an older thread, but i've just seen this from the WAI WCAG IG mailing list which i found rather...disturbing. in reply to someone mentioning the UK Govt. standard access keys

-----Original Message-----
From: Lloyd G. Rasmussen []
Sent: 15 April 2003 15:41
Subject: Re: Limited Number of possible accesskey values

They must not have tested with Window-Eyes. While in MSAA mode, alt-S
reads the status line, and alt-0 through alt-9 read part or all of the
current window. This may improve in the next release;

under the current release,, the user could go into the Window-Eyes
control panel and undefine hotkeys for windows 0 through 9 and free up some
of those AccessKeys. But alt-S is not user-configurable at present.
so...back to square 1 ?