Canon Japan has posted new firmware for the 20D

http://web.canon.jp/Imaging/eos20d/eos20d_firmware-e.html

It includes the following additions/improvements:

1. Support for the wireless file transmitter WFT-E1.

Support for the wireless file transmitter WFT-E1 allows high-speed image transfer by connecting EOS 20D and personal computers through wireless/wired LAN.

*This function works for EOS 20D when the WFT-E1 firmware is 2.0.1 or later.