[CentOS] apt package in centos 4.5

im having a problem with apt in centos 4.5 i get this error.

# rpm -Uvh apt-0.5.15cnc6-4.centos4.i386.rpm
warning: apt-0.5.15cnc6-4.centos4.i386.rpm: V3 DSA signature: NOKEY, key ID
443e1821
Preparing...                ###########################################
[100%]
        file /etc/apt/sources.list.d/centos.list from install of
apt-0.5.15cnc6-4.centos4 conflicts with file from package
centos-release-4-4.3
#
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