Something

mkdir /usr/src/kernels
cd /usr/src/kernels
wget http://www.kernel.org/pub/linux/kernel/v2.6/linux-2.6.18.tar.gz
tar -xvzf linux-2.6.18.tar.gz
cd linux-2.6.18
make menuconfig
(Exit and save)
make bzImage && make modules && make modules_install && make install
(wait long time)
grub
savedefault --default=0 --once
quit
shutdown -r now
(if the server comes back up we need to edit the grub configuration to load
 the new kernel every time):
vi /etc/grub.conf