code: function(key) {
  			var _this = this;
  			_beginTransaction(_this._engine);
  			_this._engine.removeItem(key);
  			_commitTransaction(_this._engine);
  			_this.length = _this._engine.length;
  		}
docs: /*
  Implementation to remove an item from the storage engine.
  @see YAHOO.util.Storage._removeItem