The invention relates to an arrangement and a method for configuring MO models for a cell hosted by an RBS. The cell is served by a plurality of transmission points, where each transmission point is covering a subarea of the cell. The cell is modeled by an instance of a first MO. A set of equipment of each transmission point is modeled by an instance of a second MO. The method comprises adding (110) an instance of a third MO for each subarea comprising attributes defining the usage of the transmission point covering the subarea. The method also comprises defining (120) relationships between the instance of the first MO and each instance of the third MOs, and defining (130) a relationship between the added instance of the third MO and the instance of the second MO modeling the set of equipment of the transmission point covering the corresponding subarea. FIG. 10.