Newbie Question: trigger CC from http web page (e.g. timestamp or version.html)?

I am new to cruise control.  Is it possible to confirgure cruise control to watch for a change on an html or xml page that is hosted on a web application?  For example, if http://mysite.com/version.txt or http://mysite.com/version.xml are updated (meaning a website is updated) would trigger my CC to synch, build, and run any tests.  The change could be a new version number or time stamp text.  If one is easier over the other and if you can share an example that would be great.