How to ouput a text as xhtml format in AIF

Dear Gurus:

    Would you like to help me on output a text as xhtml format in AIF?

    E.g.  i would like to output a text as  "M²M" ,the text is passed from one field of  interface structure, I try to put the text as "M²M"  in the field of interface structure , but it just outputs full text "M²M" , doesn't show "M²M" as my expectation, I already set the field format as "Rich Text" and data format as "XHTML"  for the object of text field in AIF.

   Please help. thank you very much .