Is there a newer version of the wiki software? That might help. I noticed that en.wikipedia.org has a new WYSIWYG editor, I think it's in beta.
It seems we are on
version 1.19.0 of the MediaWiki software, but the latest version is
1.21.1. No idea what changes have been made between versions or what effort it entails to upgrade, but I imagine even just updating to the latest 1.19 version would be useful.