Problem with UART. Please help!

I am using cc2530 with z-stack. Currently I exploring UART drivers. I took "SensorDemo" as basic application.

I have switched off compile options ZTOOL_P1 and MT_TASK because they also take use of UART.

Then I initialize UART:

First I prepare the callback function:

void UART_Multiplexor_in ( uint8 port, uint8 event )

  {  

   HalLcdWriteString( "Something good", HAL_LCD_LINE_3 );  

   switch(event)  {    

      case HAL_UART_RX_FULL:      

      break;    

      case HAL_UART_RX_ABOUT_FULL:      

      break;    

      case HAL_UART_RX_TIMEOUT:      

      break;    

      case HAL_UART_TX_EMPTY:      

      break;  

}

 }

Then I make task initialization:

void UART_Multiplexor_initUART(void) {

  HalUARTInit();

  halUARTCfg_t uartConfig;    

   uartConfig.configured           = TRUE;    

   uartConfig.baudRate             = HAL_UART_BR_38400;    

   uartConfig.flowControl          = TRUE;    

   uartConfig.flowControlThreshold = 48;    

   uartConfig.rx.maxBufSize        = 128;    

   uartConfig.tx.maxBufSize        = 128;    

   uartConfig.idleTimeout          = 6;    

   uartConfig.intEnable            = TRUE;      

   uartConfig.callBackFunc         = UART_Multiplexor_in;        

   HalUARTOpen (UART_MULTIPLEXOR_PORT, &uartConfig);

}

Ater that I start debugging my application. I make break point at the beginning of callback function UART_Multiplexor_in.

Unfortunately I see that the code of function is never reached.

I send data to application through serial cable, but function UART_Multiplexor_in is never called.

What am I doing wrong?

Please help!