[CentOS] Why are multiple architecture rpms installed?

Wed Mar 4 12:47:51 UTC 2009
Marten Lehmann <lehmann at cnm.de>

Hello,

I noticed, that whenever I install a package on CentOS 5.x, rpms for 
multiple architectures are installed:

yum install sqlite-devel
Loading "fastestmirror" plugin
Loading mirror speeds from cached hostfile
  * base: centos.intergenia.de
  * updates: centos.intergenia.de
  * addons: centos.intergenia.de
  * extras: centos.intergenia.de
base                      100% |=========================| 1.1 kB    00:00
updates                   100% |=========================|  951 B    00:00
addons                    100% |=========================|  951 B    00:00
extras                    100% |=========================| 1.1 kB    00:00
Setting up Install Process
Parsing package install arguments
Resolving Dependencies
--> Running transaction check
---> Package sqlite-devel.x86_64 0:3.3.6-2 set to be updated
---> Package sqlite-devel.i386 0:3.3.6-2 set to be updated
--> Finished Dependency Resolution

Dependencies Resolved

=============================================================================
  Package                 Arch       Version          Repository        Size
=============================================================================
Installing:
  sqlite-devel            x86_64     3.3.6-2          base 
260 k
  sqlite-devel            i386       3.3.6-2          base 
260 k

Transaction Summary
=============================================================================
Install      2 Package(s)
Update       0 Package(s)
Remove       0 Package(s)

Total download size: 520 k
Is this ok [y/N]: y
Downloading Packages:
(1/2): sqlite-devel-3.3.6 100% |=========================| 260 kB    00:01
(2/2): sqlite-devel-3.3.6 100% |=========================| 260 kB    00:01
Running rpm_check_debug
Running Transaction Test
Finished Transaction Test
Transaction Test Succeeded
Running Transaction
   Installing: sqlite-devel                 ######################### [1/2]
   Installing: sqlite-devel                 ######################### [2/2]

Installed: sqlite-devel.x86_64 0:3.3.6-2 sqlite-devel.i386 0:3.3.6-2
Complete!


Thats pretty annoying, because an "rpm -qa | grep sqlite" only shows the 
package name, not the arch:

sqlite-3.3.6-2
sqlite-devel-3.3.6-2
sqlite-3.3.6-2
sqlite-devel-3.3.6-2

When I later want to remove rpms, I always have to mention both archs 
explicitly:

rpm -e sqlite-3.3.6-2.i386
rpm -e sqlite-3.3.6-2.x64_86

And sometimes packages have arch i686 as well.

Or I get an error:

rpm -e sqlite
error: "sqlite" specifies multiple packages

First I thought, that this might be an issue due to 32bit compatibility. 
But then I remembered, that I used CentOS 4 on 64bit, too, and there was 
no such problem.

How can I get rid of it?

Kind regard
Marten