Excellent! I added the suggested line and got a message about how Element.pm couldn't be found in the include path. The library wasn't installed on the server, and the reason my quick hack (uploading TreeBuilder.pm to my home directory) didn't work is that it's dependent upon the rest of the library. Of course...

I didn't know fatalsToBrowser existed, but it's ever-so-convenient.

My script works now. Thanks to both of you.

Jake