All field name labels and value lists blank

We just upgraded from FileMaker Server 9 to FileMaker Server 11 and I ran PHP Site Assistant for the first time on this new server to create an input form for one of our databases. I've got the PHP Site Assistant pages up and running on our server and it works fine except for one problem. All of the field name labels and value list labels are blank - completely empty. So the fields are showing up and work fine, but there is no text saying which field is which or which checkbox is which. I've attached a screenshot in case that helps.

Any idea of what I can do to pull in all the labels? I set up quite a few PHP Site Assistant forms with FileMaker Server 9 and I've gone hunting through the code on this one to see if I can figure out where it's going wrong, but am at a bit of a loss.

Thanks for your help - it's much appreciated.