SD crashes when using Orca

[Hermann]

Hi,
on my notebook I'm working with Ubuntu Gutsy, Orca 2.20.1 and SD 0.6.4.
Almost every day I experience a crash of SD while reading text with 
Orca.
The hard drive starts spinning and Orca stops reading; braille is still 
there.
ps aux |grep speech-dispatcher
shows that SD has gone.
The logfile shows little information: Either it tells that the 
connection has been closed, or it reports a new start, but stops after a 
few lines. These lines are the initial ones, e. g. loading configuration 
logging to file and Espeak module is loaded. But then there are no more 
entries.
I have to restart SD, and then the crash does not happen again.
I use Espeak as the only loaded module (Espeak, not Espeak-Generic).
On my desktop machine I don't use Orca because I've installed a text 
Linux, and there SD is working stable (I use it with several programs, 
Speakup, Emacs with Speechd-el, Suse-blinux and a SD module of brltty).
Any ideas why that crash occurs?
Regards
Hermann

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