There is WM_DEADCHAR, I was suprised to find today. Another ray of hope
for the now almost abandoned state machine. In a one last attempt to
save it I experimented by trowing WM_DEADCHAR/WM_SYSDEADCHAR in the mix.
With sadness I have to report that I was unable to find any key sequence
that generates these two events. WM_DEADCHAR effectively pronounces the
keyboard state machine ... dead.