projectToWebMercator - Transverse_Mercator (27700)

[KCCGIS_Team]

I want to use a Transverse Mercator not a Web Mercator.

The Web Mercator Easting, Northing returned are approx 120m out

The code

gsvc = new GeometryService("http://tasks.arcgisonline.com/ArcGIS/rest/services/Geometry/GeometryServer");

        map.on("click", projectToWebMercator);

        function projectToWebMercator(evt) {

          map.graphics.clear();

          var point = evt.mapPoint;

          var symbol = new SimpleMarkerSymbol().setStyle("diamond");

          var graphic = new Graphic(point, symbol);

          var outSR = new SpatialReference(27700);

Does anyone know a projectToTransverseMercator method???

Thanks,

Clive