UART ISR() not triggering with RTX/ADUC7020

Hello all,

I'm using RTX and ADUC7020 processor and have a problem with the UART ISR routine where the ISR isn't triggering when UART data is sent to it.

In my main(), I have:

        GP1DAT |= 0x8C000000;
        REFCON = 1;

        //Set Baud for 9600bps
        COMCON0 = 0x80; //Set DLAB to access COMDIV
        COMDIV0 = 0x88; //Low byte
        COMDIV1 = 0x00; //High Byte
        COMCON0 = 0x03; //clear DLAB and set serial for 8,N,1

        COMIEN0 = 0x07; // enable interrupt when buffer is full during a reception.
                        // enable interrupt when buffer is empty during a transmission
                        // enable generation of an interrupt if any of COMSTA0[3:0] is set.
        IRQEN |= 0x4000;

In my rtx_config.c, I have changed the following from the default:

/*--------------------------- IRQ_Handler -----------------------------------*/

// User Interrupt Functions
//extern __irq void IRQx (void);               // User IRQx Function
extern __irq void IRQy (void);                 // User IRQy Function

//#define mIRQx       0x00000080               // User IRQx Mask
#define mIRQy       0x00004000                 // User IRQy Mask


__asm void IRQ_Handler (void)
{
   // Common IRQ Handler
        PRESERVE8
        ARM

        STMDB   SP!,{R0}                       ; Save R0
        LDR     R0,=__cpp((U32)&IRQSTA)        ; Load IRQSTA Address
        LDR     R0,[R0]                        ; Load IRQSTA Value

//      TST     R0,#mIRQx                      ; Check IRQx Flag
//      LDMNEIA SP!,{R0}                       ; Restore R0
//      LDRNE   PC,=__cpp(IRQx)                ; IRQx Function

        TST     R0,#mIRQy                      ; Check IRQy Flag
        LDMNEIA SP!,{R0}                       ; Restore R0
        LDRNE   PC,=__cpp(IRQy)                ; IRQy Function

        TST     R0,#(SWI_BIT :OR: RTOS_TIMER_BIT) ; Check OS IRQ Flag
        LDMIA   SP!,{R0}                       ; Restore R0
        LDRNE   PC,=__cpp(os_clock_interrupt)  ; OS Clock IRQ Function

        LDR     PC,=__cpp(os_def_interrupt)    ; OS Default IRQ Function
}

And finally, I have the ISR function that's also in the same source as main()

__irq void IRQy(void)
{
    /*if (IRQSIG & 0x00000008)
        {
        timer1_handler();
    }*/

        if (IRQSIG & 0x00004000)
        {
                uart_handler(); // break point here
        }
}

I have a break point on uart_handler() but it doesn't hit when I send UART data to it. I have a non RTX version that's configured the same and the break point hits everytime. Is there something I forgot to do? Any help is appreciated.