I am running a Centos box on a Dell R410 with a quad core processor. Currently I am running kernal version 2.6.18-238.el5PAE (Jan 13, 2011). I am looking to upgrade to 2.6.18-238.12.1.el5PAE which is May 2011. I tried running yum update kernal but no packages were found. Any help would be great.