During a radio link setup or reconfiguration or addition procedures, a serving radio network controller SRNC sends a request or prepare message to a drift radio network controller DRNC with a slot format information element IE, to which the DRNC sends a reply. During a physical channel reconfiguration process the DRNC sends a request to the SRNC with the slot format IE. In all cases, the DRNC uses the IE to determine the slot format for its fractional dedicated physical channel, and reconfigures it with the node B according to the IE.