cannot type any letters into praat

[Saser]

ubuntu 9.04
praat 5.1.0-3

I cannot type letters into praat, and I have found how to solve this problem according to the official site of praat.

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= http://www.fon.hum.uva.nl/praat/download_linux.html
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On Ubuntu, Fedora, or Mandriva, the static edition is sometimes reported to have the problem that you cannot type any letters into it. When Praat is started from the command line, there will be a long error message starting with something like "Unknown keysym name: osfActivate".

The cause of the problem is that Motif expects that the file XKeysymDB is located in /usr/X11R6/lib/X11/, but on these distributions XKeysymDB is actually located in /usr/share/X11/.

If you can become root, you could type XKEYSYMDB=/usr/share/X11/XKeysymDB into the file /etc/environment. Or you could simply copy or link XKeysymDB to the expected location with

   cp /usr/share/X11/XKeysymDB /usr/X11R6/lib/X11/

or

   ln -s /usr/share/X11/XKeysymDB /usr/X11R6/lib/X11/

If you do any of these tricks, it will work for all users on your computer. If you cannot become root, you could include

   export XKEYSYMDB=/usr/share/X11/XKeysymDB

in your .login or cshrc file.