Okay, did that. Got this:
[root@louks php-5.3.28]# yum install libxml2 libxml2-devel
Loaded plugins: fastestmirror, priorities, security
Loading mirror speeds from cached hostfile
* atomic: mir01.syntis.net
* base: mirror.sov.uk.goscomb.net
* extras: centos.serverspace.co.uk
*...