Thread:Extension talk:Lingo/Can't get it to work at all/reply (7)

Ok, I guess this is the problem then. Lingo depends on the DOM module. It is part of the standard PHP packages these days, so your admins should be able to enable it.

Just googled Quercus. It might not be so easy to just turn on the DOM module after all. Apparently Quercus is a relatively new PHP implementation in JAVA and may not yet have the module.