I'm with mister_e -

ALWAYS use the hardware USART if your PIC has one!
Use a crystal when you use RS-232.

The default baud rate of an XPORT is 9600 baud.
The XPORT is a 3.3V device. Are you running it off 3.3V?

You should use a level shifter (like a 74HC gate) between the XPORTs output and the PICs input to insure that the output level of the XPORT is high enough for the PIC. In a pinch, you can use a 1K pull up resistor (to 5V) on the line connecting the ouput of the XPORT to the PICs input. Since the XPORT is 5V compliant, you don't need to do anything with the line connecting the output of the PIC to the XPORT.