Please have a look on this dialog
http://www.daisy.org/forums/viewtopic.php?f=16&t=58
As a linux-fan i am not very happy with the answer i received from Romain but he also wrote:
"Finally, note that we'd be more than happy to assist anyone who'd volunteer to contribute a Linux TTS adapter for the Narrator!"
So this is my feature request

regards
wally
regards
Juergen