Canon has issued firmware updates for its EOS-1D Mark III, 1Ds Mark III and 5D Mark II cameras to provide compatibility with the wireless file transfer units. The 1D series cameras gain compatibility with the WFT-E2 II unit while the 5D Mark II gains WFT-E4 II support and lower noise when shooting Bulb exposures. Meanwhile the WFT-E2 and E2A firmware is also updated to allow use with the 1D Mark IV.

http://www.dpreview.com/news/0912/09...onfirmware.asp