Hello,
In GTK2, on Linux at least, you can change the keyboard mapping for any action that has a menu item by hilighting the item with your rodent, and pressing the appropriate keys.
Unlike GTK+ (i.e. version 1.x), this is disabled by default :-/ You need to add the following line to ~/.gtkrc (or wherever you configure the theme on Windows)
I've searched my system and found several gtkrc-files. I appended the line
gtk-can-change-accels = 1
in each of them in succession with no - ehm - success.
I think the bindings are save in a scheme file called menurc or something. If the above doesn't work, you might be able to edit that file by hand.
I've found such a file for dia and gimp. Changing shortcuts works in gimp, BTW. I really like that feature in gimp. I noticed that dia and gimp would create some directories .dia and .gimp-2.0 in my 'home' inkscape creates an Inkscape-direcotry where preferences.xml is stored. But this does not contain a menurc nor gtkrc.
In gimp there is an option in the preferences whether gimp should use the dynamic shortcuts. So it seems to me that gimp is able to enable that feature from within!?
best Steffen