wlan only works at boot

Hello,

wlan 0.2.2 running on a Debian sid 2.6.12 ppc iBook

I can only get it working on boot. I have a wlancfg-mynet correctly
configured with WEP and all, and it works when I boot. But if I do
/etc/init.d/wlan stop, and then start again, all I get is:

Starting WLAN Devices: FATAL: Module wlan0 not found.

but:
# grep wlan0 /etc/modules.conf
alias wlan0 prism2_usb

and, that prism2_usb module is already loaded anyway ( I tried rmmod it
first, same error ). I realize this may be distro specific, but I did
what step C) in the README said. I can't modprobe wlan0 from the shell
either ( but obviously, modprobe prism2_usb does work ).

TTimo