Pytesser only digits recognition

Last time I needed some Python library which recognizes digits from image. I decided to use Pytesser which is wrapper for tesseract.exe - program developed firstly by HP then by Google.
It worked fine with standard text examples.
I had few images containing only digits. They came from really simple captchas (with removed noises and so on..). I was using pytesser function image_to_string and getting some characters, comas, ...:/
I was trying to find option to read only digits. When i got this option it didnt work. I realized, that standard Tesseract within pytesser doesnt support them.
Sollution is: Get the latest version of Tesseract from http://code.google.com/p/tesseract-ocr/downloads/list .
Install it in pytesser directory (for me it was C:/Python27/Lib/pytesser). It will change old tesseract.exe to new one.
Find that line in pytesser.py :
args = [tesseract_exe_name, input_filename, output_filename]
Change it to:
args = [tesseract_exe_name, input_filename, output_filename, 'nobatch', 'digits']

For me it works fine!
PS:

That configuration recognizes also 'dot' and 'minus'. If You don't want that functionality then go into tessdata\configs directory, find digits file, open it and change:
tessedit_char_whitelist 0123456789.-
into
tessedit_char_whitelist 0123456789