code: function(options, layer) {
          OpenLayers.Format.GML.prototype.initialize.apply(this, [options]);
          this.layer = layer;
          if (this.layer.featureNS) {
              this.featureNS = this.layer.featureNS;
          }    
          if (this.layer.options.geometry_column) {
              this.geometryName = this.layer.options.geometry_column;
          }
          if (this.layer.options.typename) {
              this.featureName = this.layer.options.typename;
          }
      }
docs: Constructor: OpenLayers.Format.WFS
  Create a WFS-T formatter. This requires a layer: that layer should
  have two properties: geometry_column and typename. The parser
  for this format is subclassed entirely from GML: There is a writer
  only, which uses most of the code from the GML layer, and wraps
  it in transactional elements.
  
  Parameters:
  options - {Object}
  layer - {<OpenLayers.Layer>}