Discussed in the forums here: http://forums.devkitpro.org/viewtopic.php?f=23&t=1425
dswifi's Wifi_Update() may be called simultaneously as part of the fifo handler and dswifi's IRQ_TIMER3 timer, leading to corruption of WifiData, since the fifo handler is called with REG_IME set.
This patch adds a flag to the Wifi_Update() signature so that it can be instructed to not check for received...
Apologies for neglecting this as long as I have, but I have updated the WEB conversion from the GBF dated 2008-08-19.
You can download the new conversion at http://sourceforge.net/project/showfiles.php?group_id=101329&package_id=110948.