PhpDig.net - Optimized Search Mod

Does the optimized search mod work on the latest version? I am using version 1.8.9-rc1 and get the following error when trying to use other_search.php:
Fatal error: Call to undefined function: phpdigstripaccents() in .../htdocs/search/libs/other_search_function.php on line 122

The function is mentioned in the docs but I cannot find it in any of the code. Grepped through all of it. I have commented out the function call as it is not used anywhere else but this mod.

I am really only interested in ordering my search results by date. Installing this mod seems to be a prerequisite to getting that to work. If you know of any other way to order results by date descending, please help.

Thank you
khoisan