Sequence diagrams are simple and easy to understand. However, keeping them up-to-date during the development phase of a project can be onerous, sometimes even impeditive.
To make this process easier, I've developed an automatic diagram generator that receives XML as input and ouputs an HTML page with the diagram.
While still not fully working on Internet Explorer, the generator already makes life easier for those responsible in maintaining this kind of diagrams. We welcome anyone with the patience and desire to make the CSS changes need for it to work on IE.
Also, fully compliance with UML 2.0 is still under development. Anyone interested in working in these fields is more than welcome to join the team. And if you have a patch on add-on to send, feel free to do so. Just send an e-mail to thiago.henrique.mata@gmail.com
The example I posted is the story of "Three Little Pigs". It should give you a view of how the generator works and also entertain you a little bit. Change the XML as you please to generate other diagrams of your own.
And remember, this is free software, and as such, I can give you no warranty. Use it at your own risk. It's not for the faint of heart.
For external use try this link and see the HTML code. To internal use download from here.
Special thanks to Raphael Melo and Igor Moreno for helping.