Intra-enterprise wireless handset (WH) calls between WHs operating in a wireless local area network (WLAN) are established directly between the WHs via a call connection that is maintained within the LAN without being routed through the cellular network (CN). This eliminates the cost of placing and maintaining calls through the CN for intra-enterprise calls, and also enables use of capabilities that are available in the enterprise telecomm equipment. Upon detection of a trigger condition, if and when it is more likely that a complete vertical handover (VHO) may be needed, the call connection between the WHs in the LAN is replaced by one that is routed through the CN. Thereafter, a VHO may occur (if at all) upon detection of a radio handover condition.

 
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> Method for controlling a hands free system, radio apparatus, and hands free apparatus

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