11. A multi-radio access technology (multi-RAT) wireless transmitter/receiver unit (WTRU), comprising:a processor configured to:
configure a primary radio connection of a RAT of a first type associated with a radio resource control (RRC) connection, and
configure a secondary radio connection of a RAT of a second type based on received configuration information of the RAT of the second type, wherein the primary radio connection and the secondary radio connection are associated with the RRC connection; and
a wireless transmit/receive unit configured to:
receive the configuration information to configure the secondary radio connection of the RAT of the second type, and
receive control information related to the RAT of the second type using the primary radio connection,
the processor is configured to determine that a radio link failure has occurred on the RAT of the second type, and
the wireless transmit/receive unit is configured to transmit an RRC message using resources of the RAT of the first type based on the determined radio link failure.