CMSIS UART driver Infineon XMC4800 IRQ not registered

I'm using RTX on the new XMC devices and I discovered a problem with sending over UART.

The KEIL UART driver defines the TX IRQ in uart.c as

#if (RTE_UART0 != 0)
#if (UC_SERIES == XMC14)
  void IRQ9_Handler() {
    UART_IRQHandler (uart[0],USIC0_0_IRQn );
  }
        void IRQ10_Handler() {
    UART_IRQHandler (uart[0],USIC0_1_IRQn);
  }
#else
  void USIC0_0_Handler() {
    UART_IRQHandler (uart[0],USIC0_0_IRQn );
  }
        void USIC0_1_Handler() {
    UART_IRQHandler (uart[0],USIC0_1_IRQn);
  }
#endif
#endif

But in the xmc4800.h and startup_xmc4800.s file (from the pack) the IRQ handlers are named different:

#define IRQ_Hdlr_84  USIC0_0_IRQHandler

EXPORT  USIC0_0_IRQHandler      [WEAK]

This leads to an unhandled IRQ exception.

Is this a bug in the pack's files or what am I doing wrong?
Should the xmc4800.h file be modified by µVision after I have configured the UART?
Of course I can disable the write protection of xmc4800.h and add the correct IRQ handler,
but that's not the best way in my opinion.

Any help is appreciated.

Michael