I couldn't figure out a way to do it using only the XML, but here's how to do it programmatically.
In my life cycle adviser, I edited the following code:
Code:
final ActionCommand ac = window.getCommandManager().getActionCommand("priceSourceHCommand");
window.getMenuBar().getControl().getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(ac.getAccelerator(), "priceSourceHCommand");
window.getMenuBar().getControl().getActionMap().put("priceSourceHCommand", ac.getActionAdapter());
If anyone knows a way to do this declaratively, please speak up.