[Mediawiki-l] How to change browser keyboard shortcuts?

[Raimund Sudermann, CCDS GmbH]

I would like to change one shortcut of my Mediawiki:
ctrl+o on mac works as "log out" in the browser, which is anyoing if 
you are used to the shortcuts of the pico command line editor, in which 
it works as "save" (write out).

Any suggestions where I can change the shortcut?
I found some "accesskey" code but not for the letter "O".

Regards,
Raimund