Keybord short cuts same as quotes on mac os x

Hi guys, I have had long time trouble with the keyboard short cut alt-shift-q for french quotes on my Mac OS X keyboard as if I use them in WP tiny mce, it formats the text as quotation, so I can not use the french quotes only on a word. Now, with 3.5.1 I do have the same with german quotes, which I get on my Mac keyboard at alt-shift-w. I am only able using the wrong english quotes. Thats not acceptable. How do I disable such short cuts within WordPress 3.5 and on?