Yeah, I knew there was a cleaner way to express it (we should send those guys a freebie of PHP Cookbook :-). I'd thought about turning it into an XML service, but the big problem is still data protection (which, as you say, is a problem for any client-size graphing app).
I'm back to looking at server-side charting software. I wish there were a Perl XS wrapper to Ploticus, and may eventually wish my way into a text editor to make it so.