Updating extensions after PHP upgrade on CentOS 5.6

[Shawnosaurus]

I'm completely new to pecl, yum, rpm, packages and all the stuff required to get this done, so I'm hoping some of you smarter more experienced people can help me out. I only have a vague notion of what I'm doing.

I upgraded PHP 5.3.3-26.el5_11 to 5.4.45-3.el5.remi based on this article: https://kb.odin.com/en/115833

After upgrading, I'm getting PHP warnings:

Unable to initialize module
Module compiled with module API=20090626
PHP compiled with module API=20100525
Unable to load dynamic library
undefined symbol: php_checkuid in Unknown on line 0

The solutions described in another thread are to reinstall or update the extensions.

Searching around, I have tried commands like:

$pecl install ldap
No releases available for package "pecl.php.net/ldap”
install failed

$ pecl upgrade ldap
No releases available for package "pecl.php.net/ldap"
install failed

$ yum update php-mcrypt
Package(s) php-mcrypt available, but not installed.
No Packages marked for Update

I'm at a loss here, and I don't want to keep running commands as root when I don't know what I'm doing, or even what directory I'm supposed to be in. Can someone provide detail on how to do this please?

Here are the full warnings I'm getting:

PHP Warning: PHP Startup: ldap: Unable to initialize module
Module compiled with module API=20090626
PHP compiled with module API=20100525
These options need to match in Unknown on line 0
PHP Warning: PHP Startup: mcrypt: Unable to initialize module
Module compiled with module API=20090626
PHP compiled with module API=20100525
These options need to match in Unknown on line 0
PHP Warning: PHP Startup: Unable to load dynamic library '/usr/lib64/php/modules/odbc.so' - /usr/lib64/php/modules/odbc.so:
undefined symbol: php_checkuid in Unknown on line 0
PHP Warning: PHP Startup: PDO_ODBC: Unable to initialize module
Module compiled with module API=20090626
PHP compiled with module API=20100525
These options need to match in Unknown on line 0
PHP Warning: PHP Startup: snmp: Unable to initialize module
Module compiled with module API=20090626
PHP compiled with module API=20100525
These options need to match in Unknown on line 0
PHP Warning: PHP Startup: xmlrpc: Unable to initialize module
Module compiled with module API=20090626
PHP compiled with module API=20100525
These options need to match in Unknown on line 0