Message error with XML/SWF Charts

I'm making a web site with charts, I'm using "XML/SWF Charts", the
problem that I have is that the charts work perfectly when I'm working
locally, but when I load all files to the server and I want to see the
charts, the browser shows me the next message: This page requires
AC_RunActiveContent.js.

Does anyone to know the reason and how can I solve?

I'm using Mozila Firefox 3.6.3 and Internet Explorer 8.0.6001
Ruby 1.8.6-p287
Rails 2.3.5

Thanks and greeting.