I had a need to connect to MSSQL using PHP version 5 from a CentOS 5 server. To do this I needed FreeTDS and the module mssql in PHP. After a diligent search I found that there was no quick and easy way to install the mssql module, like “up2date install php-gd” to get GD to work from PHP.
I found a few places that had ideas and hints to make this work, but finally used the directions I found at http://www.howtoforge.com/installing_php_mssql_centos5.0 (slightly altered to fit my means) and will duplicate here so I can easily find it later.
At first I thought I needed to recompile PHP, but as it turned out I only needed to pre-compile it so that I could fetch the mssql.so, and then manually edit the php.ini to use it.