On WinXP ping.py doesn't receive icmp replies

[duanev]

On a Windows XP SP3 with current patches, ping.py can send icmp requests but cannot receive icmp replies, even with the firewall disabled. The Windows ping works fine, the ping.py threads run fine, ping.py packets get sent out on the wire and are received by other machines, but nothing gets returned to ping.py

Advanced network settings that enable specific icmp packet types do not alter this behavior. Disabling ICMP via advanced network settings does block icmp replies returned to other machines. Including python.exe in the network program exceptions also has no effect.