I have a several machines running SL 6 and I want to turn on sl-fastbugs 
repo to update the software for all the non-critical bugs.  The problem 
is the computers originally had SL 6.1 installed on them and updating 
with sl-fastbugs repo enabled updates only the software with the recent 
bug fixes.  I see that the sl-fastbugs repos exist for previous 
versions.  Is there an easy way to update all those bug fixes?

I have tried to create a repo to access a previous version but failed.  
Here is the repo file:
[sl-fastbugs]
name=Scientific Linux 6.4 - x86_64 - fastbug updates
baseurl=http://ftp.scientificlinux.org/linux/scientific/6.4/x86_64/updates/fastbugs/
http://ftp1.scientificlinux.org/linux/scientific/6.4/x86_64/updates/fastbugs/
http://ftp2.scientificlinux.org/linux/scientific/6.4/x86_64/updates/fastbugs/
ftp://ftp.scientificlinux.org/linux/scientific/6.4/x86_64/updates/fastbugs/
#mirrorlist=http://ftp.scientificlinux.org/linux/scientific/mirrorlist/sl-fastbugs-6.txt
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-sl 
file:///etc/pki/rpm-gpg/RPM-GPG-KEY-dawson

And here is the errors I got when I tried to use it:
# yum --disablerepo=\* --enablerepo=sl-6.4-fastbugs.repo update
Loaded plugins: downloadonly, priorities, refresh-packagekit, security
Repository sl-fastbugs is listed more than once in the configuration


Error getting repository data for sl-6.4-fastbugs.repo, repository not found

Thank you for any help you can give.
Paul