An apparatus, method, system and computer program product can be capable of supporting user equipment multiplexing in relay enhanced networks. The apparatus includes a unit configured to process a first data packet header element of fixed length which identifies a bearer or a logical channel; a unit configured to process a configuration parameter indicating the length of an additional second data packet header element inclusive of a length of zero, wherein a combination of the first data packet header element and the second data packet header element identifies a bearer or a logical channel of a user equipment; and a unit configured to process data of different user equipment in a transport block data packet by utilizing a packet header of the transport block data packet including a respective combination of the first data packet header element and the second data packet header element for each different combination of bearer or logical channel and user equipment.