Just for reference you can find installation instructions for CentOS 5 and WeBWorK 2.3 at http://webwork.maa.org/wiki/Installation_Manual_for_2.3_on_CentOS_5
Note that these are pretty old and out of date (e.g. you should definitely install the current version of WeBWorK 2.4; release rel-2-4-patches) but may still be of use to people installing WeBWorK on CentOS 5. In particular Ghostscript is mentioned.
Arnie
Installation
not generating hardcopy - solution for CentOS 5
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