Fedora :: Cryptic Error Message When Trying To Install Flash

I'm new to Fedora 13, although 10 years ago I fooled around a little with Red Hat 4.2 and Mandrake 7. I'm trying to install flash on my desktop. The install went as smooth as can be on my laptop, but the desktop isn't going well. First of all, My system is an AMD Phenom 9950 Quad Core in an Asus M4N78 PRO motherboard with 4 Gb of RAM, although Gnome reports it as 3.8 Gb. Video is Invidia GeForce 5500.

The Flash install goes ok until I enter the command:
"yum install flash-plugin nspluginwrapper.x86_64
nspluginwrapper.i686 alsa-plugins-pulseaudio.i686
libcurl.i686"

Once that command starts running it pops out this error message:
Error: Package: glibc-2.12-2.i686 (updates)
Requires: glibc-common = 2.12-2
Installed: glibc-common-2.12-3.x86_64 (@updates-testing)
Available: glibc-common-2.12-1.x86_64 (fedora)
Available: glibc-common-2.12-2.x86_64 (updates)
You could try using --skip-broken to work around the problem
You could try running: rpm -Va --nofiles --nodigest

I've tried the work arounds suggested by the error message and they didn't work. I tried downloading the missing file and it seems to not exist. I also tried this command:
yum downgrade glibc-common-2.12-3.x86_64

That generated this output:
Setting up Downgrade Process
Loading mirror speeds from cached hostfile
* fedora: mirror.hiwaay.net
* livna: rpm.livna.org
* rpmfusion-free: mirror.hiwaay.net
* rpmfusion-free-updates: mirror.hiwaay.net
* rpmfusion-nonfree: mirror.hiwaay.net
* rpmfusion-nonfree-updates: mirror.hiwaay.net
* updates: mirror.hiwaay.net