在CentOS服务器中，安装包的问题

一台装有CentOS服务器如下：
[root@user ~]# lsb_release -a
LSB Version: :core-4.0-amd64:core-4.0-ia32:core-4.0-noarch:graphics-4.0-amd64:graphics-4.0-ia32:graphics-4.0-noarch:printing-4.0-amd64:printing-4.0-ia32:printing-4.0-noarch
Distributor ID: CentOS
Description: CentOS release 5.6 (Final)
Release: 5.6
Codename: Final
装机时安装了MySQL-server-5.5.16-1.rhel5.x86_64.rpm 如下：
[root@user ~]# rpm -qa | grep -i mysql
MySQL-server-5.5.16-1.rhel5
MySQL-client-5.5.16-1.rhel5
MySQL-devel-5.5.16-1.rhel5
后来，发现装许多别的软件（比如postfix dovecot）时，会依赖一个mysql-libs的东西，例如：
……
Installing for dependencies:
mysql-libs x86_64 5.0.92-1.el5 CentALT 1.8 M
……
但这个也总是装不上，提示有一大堆冲突：
file /etc/my.cnf from install of mysql-libs-5.0.92-1.el5.x86_64 conflicts with file from package MySQL-server-5.5.16-1.rhel5.x86_64
file /usr/share/mysql/charsets/Index.xml from install of mysql-libs-5.0.92-1.el5.x86_64 conflicts with file from package MySQL-server-5.5.16-1.rhel5.x86_64
file /usr/share/mysql/charsets/cp1250.xml from install of mysql-libs-5.0.92-1.el5.x86_64 conflicts with file from package MySQL-server-5.5.16-1.rhel5.x86_64
……
但现在这服务器上的MySql又不能删……请问我该怎么处理这个问题？
多谢！