Need help with festival in red hat

[mooncar at libero.it]

Hello!
I have to install festival on a computer with Linux Red Hat 8. I have already installed FESTIVAL by tarball, but it speak too fast. The exact procedure that I have followed is

tar xvzf speech_tools-1.2.95.tar.gz
./configure, make, make install
tar xvzf festival-1.95-beta.tar.gz
tar xvzf festlex_CMU.tar.gz
tar xvzf festlex_OALD.tar.gz
tar xvzf festlex_POSLEX.tar.gz
tar xvzf festvox_kallpc16k.tar.gz
./configure, make, make install

It seems that all goes well, but when I run Festival it speak too fast, and if I use the command
(Parameter.set 'Duration_Stretch 2)
the result is that pronounciation in stretched, but still deformed..
Why? Has someone any idea ?

thank you 

mooncar