code: function(closeBox) {
  
          if (this.lonlat != null) {
              if (!this.popup) {
                  var anchor = (this.marker) ? this.marker.icon : null;
                  var popupClass = this.popupClass ? 
                      this.popupClass : OpenLayers.Popup.Anchored;
                  this.popup = new popupClass(this.id + "_popup", 
                                              this.lonlat,
                                              this.data.popupSize,
                                              this.data.popupContentHTML,
                                              anchor, 
                                              closeBox); 
              }    
              if (this.data.overflow != null) {
                  this.popup.contentDiv.style.overflow = this.data.overflow;
              }    
              
              this.popup.feature = this;
          }        
          return this.popup;
      }
docs: Method: createPopup
  Creates a popup object created from the 'lonlat', 'popupSize',
  and 'popupContentHTML' properties set in this.data. It uses
  this.marker.icon as default anchor.
  
  If no 'lonlat' is set, returns null.
  If no this.marker has been created, no anchor is sent.
  
  Note - the returned popup object is 'owned' by the feature, so you
  cannot use the popup's destroy method to discard the popup.
  Instead, you must use the feature's destroyPopup
  
  Note - this.popup is set to return value
  
  Parameters:
  closeBox - {Boolean} create popup with closebox or not
  
  Returns:
  {<OpenLayers.Popup>} Returns the created popup, which is also set
  as 'popup' property of this feature. Will be of whatever type
  specified by this feature's 'popupClass' property, but must be
  of type <OpenLayers.Popup>.