what to do after yum update?

[mailingliste at dreampixel.de]

Hi at all,

I have a kolab3 on centos. Yesterday I have run 'yum update' after my  
holiday and there were kolab packages updated.

Now I found many file with extension .rpmnew:

[root at kolab /]# find -name '*.rpmnew'
./etc/roundcubemail/kolab_folders.inc.php.rpmnew
./etc/roundcubemail/main.inc.php.rpmnew
./etc/roundcubemail/password.inc.php.rpmnew
./etc/roundcubemail/kolab.inc.php.rpmnew
./etc/kolab/kolab.conf.rpmnew

what should I do after the update?

with best regards
sven