> Have you considered using sudo? You can give the one command to a user account 
> with no password (if desired).
i could do that, but "login + sudo + shutdown -r now" is too complicated 
for user that has never worked with unix system :o( sudo will solve only 
the cause of the unix user that wants to reboot...

anyway, thanks for suggestion.
lubos

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Mgr. Lubos Vrbka

Center for Complex Molecular Systems and Biomolecules
J. Heyrovsky Institute of Physical Chemistry
Academy of Sciences of the Czech Republic
Prague, Czech Republic

shnek@chemi.muni.cz
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