A method and apparatus for performing state transition of a wireless transmit/receive unit (WTRU) which supports enhanced dedicated channel (E-DCH) in the CELL_FACH state is disclosed. Uplink data is transmitted via an E-DCH while operating in a CELL_FACH state. A radio resource control (RRC) signal, which includes a reconfiguration message, is received while the WTRU is assigned an E-DCH resource. A reconfiguration of the physical channels is performed according to the RRC reconfiguration message. A transition to a CELL_DCH state is performed and uplink data is transmitted in the CELL_DCH state via the E-DCH. In-synch and out-of-synch parameters are reported.