I may have found the solution already, but Is there some easier way of doing the same?

Is there any way to tell yum to automatically ignore or prefer files coming from x86_64 rpm packages over i386 packages, if both should be installed but both have same == conflicting files?

Also in the future, the system is unable unattentively update even critical packages, because there will be conflicts.

The story
Upgrading from Fedora core 6 to fc9.

Lots of conflicts when doing the "yum update" after the upgrade with the "Fedora 9 X86_64"-install-DVD has been done.

The problem comes from the fact there is both x86_64 and i386 rpm-packages installed on the system and some package, say somepackage-2.x86_64.rpm and somepackage-2.i386.rpm both have same files in them, like configuration files, man pages and so on.

Googled around, checked yum FAQ and yum bugzilla, but the solutions all need lots of handwork. :-(
Would have filed a bug in yum bugzilla, but they have made it difficult.

What helps abit, is to have
...in /etc/rpm/macros so when trying to find which rpm files conflic, rpm and yum programs will tell the architecture with the package name. (i385/x86_64)

So instead of telling:
....it will tell:
First I tried to "yum remove" the conflicting i386-packages, but it would had needed lots of handwork and besides, I will need also those i386-libraries because some programs are not compiled or even compatible with x86_64; say Firefox (i.e. Flash-plugin, java-plugin), matlab student version, and some other programs.

So what I did, was manually install the rpm packages yum had retrieved from the yum repositories:
Or if one is brave enough (and is sure what is doing):
The error log and some of the conflicts which I got when doing yum update:

I had this figured out before. I was trying to get a pure 64bit system. I believe I added the below to the yum.conf. However, even a purely 64bit system still needs 32bit libraries. What I did ultimately was a clean install with the base minimal packages. Then I removed all 32 bit packages and added the exclude to my yum.conf then tried to install the 64 bit versions of what I removed. It took some effort but I got it working. I realized it was more of a headached than it was worth later on when I could do flash or many other things due to the lack of 64bit support.

exclude=*.i386

good luck!

Yep, that is why I do not want to remove the 32 bit packages, because it is a headache to use 64bit Firefox when plugins are not working (and nspluginwrapper has SIGSEGVs too often).
Also I need to run 32bit Matlab in my system.

Would think this is indeed an old problem which would had been solved already in rpm programs.

Say, if rpm/yum would tolerate collides in multiple packages of same name, but just with different architecture suffixes. (.i386 and .x86_64). At least for files which are marked as document or configuration files in the rpm SPEC-file.

I know there is a problem because some semantically exact same configuration and document files can have automatically created comments by compiler version and platform. Therefore probably the mechanism would have to be optional and in some configuration file in /etc/rpm/ it should be told which architecture text-files are preferred if they collide and have a different checksum, and which ones are just renamed.

i.e. foobar-2.i386.rpm and foobar-2.x86_64.rpm have both a file /etc/foobar.conf
IF the checksums of foobar.conf files differs, consult /etc/rpm/arch_conflicts.conf and see what to do when there is a conflict; for example save /etc/foobar.conf as it is from x86_64 package, but from i386 package rename it to /etc/foobar.conf.i386.rpmconflict