RPM of PHP 5.3.13 are available for Enterprise Linux in remi repository.
RPM of PHP 5.4.3 are available for Fedora in remi repository and for Enterprise Linux in remi-test repository.
Read the announcement :
Use YUM to install :
yum --enablerepo=remi update php-\*
This versions will also be soon available in the official updates for:
Fedora 17 — PHP 5.4.3
Fedora 16 — PHP 5.3.13
Fedora 15 — PHP 5.3.13
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