You can find the versions of php including in various Ubuntu releases here:
Debian releases here:
and Fedora releases here:
So, both Debian 6 and Ubuntu 12.04 provide you with 5.3.x versions of php.
I don't know of a site that provides an overview of the packages in different versions of CentOS, but I do happen to know off hand that CentOS also provides php 5.3.3.