code: function(bounds) {
          var url = "";
          bounds = this.adjustBounds(bounds);
          
          // create an arcxml request to generate the image
          var axlReq = new OpenLayers.Format.ArcXML( 
              OpenLayers.Util.extend(this.options, {
                  requesttype: "image",
                  envelope: bounds.toArray(),
                  tileSize: this.tileSize
              })
          );
          
          // create a synchronous ajax request to get an arcims image
          var req = new OpenLayers.Request.POST({
              url: this.getFullRequestString(),
              data: axlReq.write(),
              async: false
          });
          
          // if the response exists
          if (req != null) {
              var doc = req.responseXML;
  
              if (!doc || !doc.documentElement) {            
                  doc = req.responseText;
              }
  
              // create a new arcxml format to read the response
              var axlResp = new OpenLayers.Format.ArcXML();
              var arcxml = axlResp.read(doc);
              url = this.getUrlOrImage(arcxml.image.output);
          }
          
          return url;
      }
docs: Method: getURL
  Return an image url this layer.
  
  Parameters:
  bounds - {<OpenLayers.Bounds>} A bounds representing the bbox for the
  request.
  
  Returns:
  {String} A string with the map image's url.