XML Database Updated Dynamically from HTML

Ok, this goes out to all the programmers that I know.

Here's my situation. I have a client where updating an XML database is TOO DIFFICULT! I mean come on! The database is located at http://www.wesdobry.com/y2/calendar.xml
Simple as ****.
The HTML interface for that page is here. http://www.wesdobry.com/y2/seminars.htm

So, I decided to setup an html page with a dynamic content updater for that database. Here's the problem. I don't know what kind of a script to write that will add an entry to an XML database. Hmmm.....

I'm thinking that this is going to be a rather intensive CGI application building process. I'm not looking too forward to this. Any ideas? Can it be done with Java Script? How about VBScript? PERL maybe?

I don't know about the whole scripting thing. She's makeing this easier on her and more difficult on me. Grr... TIA.