Does not work using the example code with XB Pro with DigiMesh firmware #28

Hi, 

From the documentation for python-xbee 2.0, I used the attached code.

Since I'm on a Windows machine, I had to tweak the code by inputting the port 
number associated with COM4. This code works when using print(ser.readline()) 
but for some reason print(xbee.wait_read_frame()) just doesn't return anything. 
I'm using XBee Pro w/ DigiMesh firmware, the latest version of pySerial, 
python-xbee, and I have the latest version of Python (3.x.x).

I also get the following error:

>>> 
Traceback (most recent call last):
  File "C:\Projects\RonakWaspmote\program\python\readCOM.py", line 14, in <module>
    print(xbee.wait_read_frame())
  File "C:\Python32\lib\site-packages\xbee\base.py", line 390, in wait_read_frame
    return self._split_response(frame.data)
  File "C:\Python32\lib\site-packages\xbee\base.py", line 222, in _split_response
    "Unrecognized response packet with id byte {0}".format(data[0]))
KeyError: 'Unrecognized response packet with id byte 144'

What could be the problem? Is it the firmware?