Torsten pointed me to this:
Just check the method #defaultDesktopCommandKeyTriplets in PasteUpMorph
and you get all command keys for the world.
Note that in Pharo there is an already fixed bug that has to be integrated (http://code.google.com/p/pharo/issues/detail?id=2964).
But neither Alt-\ nor Strg-\ does what it's supposed to do here with pharo 4.1 on linux.
Markus