identifytask returning Null with raster layer

[JimBridge]

We upgraded to 10.1 and get nullback from identifytask on maps that have a raster layer.  The layer had been ecw image but I exported the data as jpg and added the exported data as a layer.  The new jpg layer seems to display correctly but the identifytask done on all layers fails. If i remove the the raster layer idenitfytask works.  I can't test with the layer as an ecw image because I don't currently have an erdas license.

[JenniferNery · Accepted solution]

If this is an image service, you might want to use ImageServiceIdentifyTask instead http://resources.arcgis.com/en/help/silverlight-api/apiref/api_start.htm?ESRI.ArcGIS.Client~ESRI.Arc..., where you would be specifying the following parameters: http://resources.arcgis.com/en/help/silverlight-api/apiref/api_start.htm?ESRI.ArcGIS.Client~ESRI.Arc...