Hrmm I imagine
http://download.fedora.redhat.com/pub/e ... urity.html will suffice even if it is for 5.4 (I can't see anything that says and I don't have a centos box to check).
I don't know how critical what you're running is, if you can afford a few minutes downtime just install it, if it doesn't work, remove it.
If it's some mission critical stuff you can create a linode512 and install it on there, it'll cost you less than a dollar for a day.
_________________
Paid supportHow to ask for help
1. Give details of your problem
2. Post any errors
3. Post relevant logs.
4. Don't hide details i.e. your domain, it just makes things harder
5. Be polite or you'll be eaten by a grue