Perfect! Usually mnemonics are activated by Meta-$letter, e.g. Meta-C (or Alt-C) for "[C]ancel" or Meta-M for "I[m]port". That has long tradition. I've just found the I[m]port example in Evolution's (mail client) [F]ile menu. It also works that way in console twin-panel file managers Midnight Commander and almost all menu-like GUI panels in Windows applications.