Two arduinos over wifi ethernet lan

I have two arduino megas with ethernet shields (each one is "hacked" to accept the ethernet shield) I have one arduino set up as an ethernet host and the other as an ethernet client. I have had success when connecting these two over a wired channel over a router. However, I am trying to do this wirelessly and have had sporadic connection results, usually failed connections. I have a wireless system where I know that the arduinos can see each other (verified with ping testing). With further ping testing, I am able to ping the host with no problem at nearly any time, but pinging is less consistent with the client. I can sometimes ping it 30 seconds after the ethernet.begin() (if i put a large delay before client.connect() ) and I can ping it after it fails to connect to the client. I was looking through the wiznet datasheet and was considering that maybe the issue is a timeout. Other than that idea I am not really sure, any ideas would be helpful. Thanks

I'm not sure if it's widely known but there's a shield available now which makes connecting 2 or more Arduinos over Wifi a breeze.

http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1235716581