Download your updates from here:
I never have used uptodate, I have no internet at home.
Download and install like regular rpm... :-)
Bewatch upgrading glibc - its risky! That's for sure!
Perhaps its best to compile glibc like this:
rpmbuild --rebuild glibc* target=i686(orwhatever processor you have)
rpm -Uvh -glibc*
But if you destroy your installation with these instructions, don't blaim me. :-)