rkhunter does not like FC4 x86_64

[François Patte <francois patte math-info univ-paris5 fr>]

Bonjour,

Why FC4 x86_64 is not listed in /var/rkhunter/db/os.dat and why, if I 
change i386 to x86_64 on the line FC4, something changes it back to i386?

How to add a new line with FC4 x84_64 in this file?

rkhunter send a warning message (this machine can be infected) if the OS 
is not in the file os.dat and, doing so, how can we trust rkhunter in 
that case?

Thank you.
--
François Patte
UFR de mathématiques et informatique
Université René Descartes
http://www.math-info.univ-paris5.fr/~patte