Python error on CentOS 4.4

I am getting the following error when running on CentOS 4.4 with all the lastest upgrades applied:

/usr/lib/python2.3/optparse.py:668: FutureWarning: %u/%o/%x/%X of negative int will return a signed string in Python 2.4 and up
return ("<%s at 0x%x: %r>"

Everything seems to be working so I assume it is just a warning but I get that message every time I rung blockhosts.py