Ambiguous shortcut errors in Igor 7

Hi,

After upgrading my code, I can no longer use a CTRL+SHIFT+1 shortcut. I get the error

  Ambiguous shortcut: Ctrl+Shift+1


and then nothing happens.

When I comment out my menu entry


menu
    "Open panel/S1", /Q, DoWindow/K myPanel; myPanel()
end


then I get no response to CTRL+SHIFT+1. Shouldn't ambiguity mean I have 2 options for this menu entry?

There is still the line
	"Test/S1"			// Shift-Cmd-1, Ctrl+Shift+1.
in the help so I don't think this behaviour should have changed in Igor 7.