After changing LAN ja WAN addresses to static and upgrading Motorola original firmware to WR RC4 I configured the WR850G to client mode (via webif):

Configuration: updating...

wl0_mode="sta"
wl0_ssid="test"
wl0_akm="none"
wl0_wep="disabled"
Committing NVRAM ...
Reloading wireless settings ...
cat: /var/run/wifi.pid: No such file or directory

Last time I managed to configure the box to unknown state (http://forum.openwrt.org/viewtopic.php?id=3407)
I still would like to get this box working again, but how I unset this move?

I see that the Wireless interface is still on LAN side, but what mode is it in?
I can not ping any hosts connected to WR850G LAN ports from Wireless side nor other way around. At the same time both sides can ping the WR850G itself.

What does this client mode do?

I got the routed client mode to work with:

root@OpenWrt:~# nvram get wl0_mode
sta
root@OpenWrt:~# nvram get wl0_ssid
test
root@OpenWrt:~# nvram get wan_ifnames
vlan1
root@OpenWrt:~# nvram set wan_ifname=eth1
root@OpenWrt:~# nvram get lan_ifname
br0
root@OpenWrt:~# nvram get lan_ifnames
vlan0 eth1 wds0.2 wds0.3 wds0.4 wds0.5
root@OpenWrt:~# nvram set lan_ifnames="vlan0 wds0.2 wds0.3 wds0.4 wds0.5"
root@OpenWrt:~# nvram commit
root@OpenWrt:~# reboot

But shouldn't all this be set by the webif?