SElinux warning after last RHEL5 update

[Francisco José Márquez Gómez]

Hi,

I've updated some packages (included kernel) to last version available 
through update tool of RHEL5.5.

At finish, system has showed this warning:

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selinux-policy-targeted-2.4.6-279.el5_5.2.noarch
alias homedir /var/qmail/alias or its parent directory conflicts with a
defined context in /etc/selinux/targeted/contexts/files/file_contexts,
/usr/sbin/genhomedircon will not create a new context. This usually 
indicates an incorrectly defined system account.  If it is a system 
account please make sure its login shell is /sbin/nologin.
qmaild homedir /var/qmail or its parent directory conflicts with a
defined context in /etc/selinux/targeted/contexts/files/file_contexts,
/usr/sbin/genhomedircon will not create a new context. This usually 
indicates an incorrectly defined system account.  If it is a system 
account please make sure its login shell is /sbin/nologin.
qmaill homedir /var/qmail or its parent directory conflicts with a
defined context in /etc/selinux/targeted/contexts/files/file_contexts,
/usr/sbin/genhomedircon will not create a new context. This usually 
indicates an incorrectly defined system account.  If it is a system 
account please make sure its login shell is /sbin/nologin.
qmailp homedir /var/qmail or its parent directory conflicts with a
defined context in /etc/selinux/targeted/contexts/files/file_contexts,
/usr/sbin/genhomedircon will not create a new context. This usually 
indicates an incorrectly defined system account.  If it is a system 
account please make sure its login shell is /sbin/nologin.
qmailq homedir /var/qmail or its parent directory conflicts with a
defined context in /etc/selinux/targeted/contexts/files/file_contexts,
/usr/sbin/genhomedircon will not create a new context. This usually 
indicates an incorrectly defined system account.  If it is a system 
account please make sure its login shell is /sbin/nologin.
qmailr homedir /var/qmail or its parent directory conflicts with a
defined context in /etc/selinux/targeted/contexts/files/file_contexts,
/usr/sbin/genhomedircon will not create a new context. This usually 
indicates an incorrectly defined system account.  If it is a system 
account please make sure its login shell is /sbin/nologin.
qmails homedir /var/qmail or its parent directory conflicts with a
defined context in /etc/selinux/targeted/contexts/files/file_contexts,
/usr/sbin/genhomedircon will not create a new context. This usually 
indicates an incorrectly defined system account.  If it is a system 
account please make sure its login shell is /sbin/nologin.
--------------------------------------------

What is the problem??? I haven't modified nothing recently...

Regards