Adobe Reader 8 Accessibility Features

http://help.adobe.com/en_US/Reader/8.0/WS58a04a822e3e50102bd615109794195ff-7d31.html

Though Acrobat Standard provides some functionality for making 
existing PDFs accessible, you must use Acrobat Professional or 
Acrobat 3D to perform certain tasks­such as editing reading order or 
editing document structure tags­that may be necessary to make some 
PDF documents and forms accessible.

For extensive information about creating accessible PDFs and using 
accessibility features to read PDFs, visit the 
<http://www.adobe.com/go/accessibility>accessibility page of the Adobe website.

Interesting, But I find no  claim to what might conform to./Harvey
http://www.hbingham.com