Thanks for your reply.
I removed the baudrate generator setting update code in the interrupt routine and everything works fine. So something goes wrong when I update the baudrate. This is the code in the interrupt routine to update the baudrate:

	BRGCON = 0x00;
  	BRGR0 = 0x20;
    	BRGR1 = 0x00;
	BRGCON = 0x03;

I have to update the baudrate in the interrupt routine. What's wrong with this code?

Regards,
Mark