cfchart and 508 compliance

I'm looking for a way to add a text equivalent to a rendered cfchart. I've read documentation for CF11 that states "Some complex controls such as cfmap and cfchart do not include text alternatives for some image," and you cannot add an alt tag to <cfchart>. However, the same documentation states "ColdFusion charts do provide any text equivalents for non-text elements."

Adobe ColdFusion 11 - Section 508 Voluntary Product Accessibility Template

How is this achieved?