Who knows what they were thinking for the N900. However, the port of xterm for the tablets has a feature for emulating missing keys as on-screen buttons in that toolbar. Menu>Tools>Settings>Toolbar shortcut. You can add Home, End, Enter and more. See http://www.internettablettalk.com/wi...ial_xterm_Keys
anyway the CTRL button is "sticky"/toggle. Of course that's only xterm. There are other programs that use a toolbar and perhaps can/will support sticky keys.