I am a front end developer who uses Tridion from time to time (on a not very technical level) . I am looking for a way to change the document type in the Tridion 2009 rich text schema field to allow me use data-attributes (for a tooltip popover). At the moment the rich text fields are set to be either Strict or Transitional. I need it to be set to HTML5 (I know this can be done in 2011 with some changes. What changes I'm not sure.) As it stands data-attributes are stripped out by default on publish in either of these modes. Selecting HTML5 corrects this issue.
Any help would be greatly appreciated.