An apparatus, such as a base station, transmitting signaling information in a cellular communication system whereby a plurality of shared uplink transmission resources is divided into sets of mutually exclusive transmission resources. The apparatus comprises means for granting uplink resources to a wireless subscriber communication unit via a grant message for uplink transmission; means for receiving an uplink transmission from a wireless subscriber communication unit; means for deriving an uplink code resource identifier from the uplink transmission or the grant message; means for assigning at least one downlink code sequence used to carry downlink signaling information associated with the uplink transmission and which is derived using the uplink code resource identifier; and means for transmitting a downlink transmission comprising the at least one downlink code sequence to the wireless subscriber communication unit.