Wireless stops working on resume under Feisty

After I resume from suspend to ram, my wireless networking card no longer seems to work. It sees the network, but when I try to connect to it, the little icon with the two grey dots appears, as usual, then one turns green, as usual, then it tells me that it cannot connect. and shows the picture of the two computers with the line through it.

The only way I have been able to resume a connection is to reboot my computer.

I am running Ubuntu Feisty on a Dell Inspiron 6000, with an Intel PRO/Wireless 2200BG Networking card. My processor is Pentium M. I have 1 gig of ram.