Could someone advise on how to enable the json_encode function in PHP?
I have a clean install of Centos 5.6 and have just installed Virtualmin.
Does anyone know the next steps to take?
As in http://www.php.net/manual/en/json.requirements.php
Requirements
There is no installation needed to use these functions; they are part of the PHP core.
Just PHP >= 5.2.0
Edit: saw in a comment also this
On RHEL5/CentOS5 add the EPEL repository (http://fedoraproject.org/wiki/EPEL).
After that, installation is as simple as:
sudo yum install php-pecl-json
Don't know if this apply for your question, I don't have a Centos server...
For Ubuntu:
sudo aptitude install php5-json