apacheのVirtualHostの設定をコピって起動したら、
# service httpd start
httpd を起動中: [Fri Jan 20 18:25:47 2012] [warn] _default_ VirtualHost overlap on port 80, the first has precedence
[Fri Jan 20 18:25:47 2012] [warn] _default_ VirtualHost overlap on port 80, the first has precedence
設定を見てみると
<VirtualHost *:80>
#...
</VirtualHost>
<VirtualHost *:80>
# ...
</VirtualHost>
を
NameVirtualHost 1.2.3.4
<VirtualHost 1.2.3.4>
# ...
</VirtualHost>
NameVirtualHost 1.2.3.5
<VirtualHost 1.2.3.5>
# ...
</VirtualHost>
のように変更すると警告はでなくなった。
CentOSの６．０も６．２
httpd.i686 2.2.15-15.el6.centos
なので何か忘れてるらしい。