Keen on updating to 11.20 I just tried those lines:
rpm -Uvh --nodeps $(repoquery --location glibc)
yum update
yum reinstall xvidcore
yum update
/opt/kaltura/bin/kaltura-config-all.sh
And that worked for me.
Short meaning: I manually updated the glibc from 2.6 to 2.8 without looking for a breaking dependency which would have been the xvidcore package. After that I updated the whole bunch and to be sure reinstalled the xvidcore again, hoping it will find the new glibc if anything changed.
So far it seems to work.