Apparatus, and an associated method, for enhancing VoIP communication services at a selected QoS level in a radio communication system. Apparatus is embodied at a MAC (Medium Access Control) layer of the communication system by which selectably to cause retransmission and re-ordering of data communicated pursuant to effectuation of the communication service. A service request generator generates a service request that requests initiation the communication service in which data retransmission is effectuated at the MAC layer. And, a buffer is utilized at the MAC layer at which data is re-ordered, if necessary, to place the data in form for delivery to higher logical layers defined in the communication system.