Writing formulas with <math> does no longer work on the Wiki. Old formulas are still shown, but new formulas get the error message: Failed to parse (Missing texvc executable; please see math/README to configure.) See for example and try it out there https://wiki.documentfoundation.org/User:Regina#Sandbox http://wiki.openoffice.org/wiki/User:Regina#Sandbox has the same problem. But hopefully here is someone with a solution.
Should be fixed now, was missing variable in configuration and missing helper tool.
Thanks, it works now for me.