How do you send pings through a restrictive firewall?

[The CyberShot]

Hello guys, I just recently found out that you can't ping computers if you are behind a restrictive proxy that you are needed to connect to before you do any packet sending. I tried using the 'proxycfg' command to set the proxy (127.0.0.1:9666 in my case) but that didn't work. I did a little googling and came up with a neat app called TCPPing tcping.exe - ping over a tcp connection TCPPing can ping computers over a TCP connection. Just what I wanted, but I need the pings to go through my proxy server. Any idea how I could do that? BTW, I also tried Proxifier, but that didn't work either. Help please!