PAE kernel missing in distro

I have just downloaded and installed latest 32-bit distro.

Since the server has 8GB of RAM, I tried to update the kernel to PAE version to be able to use memory over 4GB. The response from yum was:

# yum install kernel-PAE
Loaded plugins: fastestmirror, kmod
Loading mirror speeds from cached hostfile
Setting up Install Process
Resolving Dependencies
--> Running transaction check
---> Package kernel-PAE.i686 0:2.6.18-274.el5 set to be installed
--> Finished Dependency Resolution

Dependencies Resolved

================================================================================
 Package             Arch          Version                  Repository     Size
================================================================================
Installing:
 kernel-PAE          i686          2.6.18-274.el5           base           18 M

Transaction Summary
================================================================================
Install       1 Package(s)
Upgrade       0 Package(s)

Total download size: 18 M
Is this ok [y/N]: y
Downloading Packages:
http://yum.freepbxdistro.org/centos/5.7/os/i386/CentOS/kernel-PAE-2.6.18-274.el5.i686.rpm: [Errno 14] 
HTTP Error 404: Not Found
Trying other mirror.


Error Downloading Packages:
  kernel-PAE-2.6.18-274.el5.i686: failure: CentOS/kernel-PAE-2.6.18-274.el5.i686.rpm from base: 
[Errno 256] No more mirrors to try.

Is PAE kernel unsupported or should I maybe add another repository to check?

Why not just install the 64 bit distro?

Well, to tell the truth, the only reason is that I don’t know how tested the 64-bit version of the distro really is?

For my main production server I am still running one of the first distro versions (32 bit) and it is rock-solid.
Later distro versions have their quirks and I’m still getting used to 2.10.