chkrootkit reports INFECTED :(

[Mikhail E. Zakharov]

Hi!
Running chkrootkit on newly installed FreeBSD 5.0 got:

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Checking `basename'... not infected
Checking `biff'... not infected
Checking `chfn'... INFECTED
Checking `chsh'... INFECTED
Checking `cron'... not infected
Checking `date'... INFECTED
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Checking `ls'... INFECTED
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Checking `ps'... INFECTED
Checking `pstree'... not found
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What does it mean? Is my system really hacked?