Rendering or Exporting a SSRS 2008 report to RTF

I am using Microsoft.ReportViewer to display SSRS reports from my C# desktop application. The ReportViewr by default provides the 3 modes of export features, 1. Excel. 2. Word, 3. PDF. Now we want another export capability of RTF. Does any one have any idea how to convert the SSRS reports to RTF format?