Duplicated rpms (x86, x64) on default CentOS 5.6 istallation

rpm -qa --queryformat='%{n}-%{v}-%{r}.%{arch}¥n' | grep '¥.i[3456]86$' | sort

device-mapper-1.02.55-2.el5.i386
e2fsprogs-libs-1.39-23.el5_5.1.i386
glibc-2.5-58.el5_6.4.i686
libgcc-4.1.2-50.el5.i386
libhugetlbfs-1.3-8.2.el5.i386
libselinux-1.33.4-5.7.el5.i386
libsepol-1.15.2-3.el5.i386
libtermcap-2.0.8-46.1.i386
mkinitrd-5.1.19.6-68.el5_6.1.i386
ncurses-5.5-24.20060715.i386
ncurses-devel-5.5-24.20060715.i386
parted-1.8.1-27.el5.i386
readline-5.1-3.el5.i386