How do I properly use MHS?

Maybe I do something wrong?
This is what I did:
I could start and set it up.
Then on the N900 I choose the AddHoc connection with created before with MHS.
After a while the AddHoc icon gets steady.
On my Laptop (Kubuntu 10.10 as well as Win XP) I search for a Wifi connection with the same name.
Both OS on the laptop can find it and try to configure it, but they never get an IP.
I even tried it under linux manually with "dhclient wlan0", but it runs into an timeout.

Note:
I already for a while use the USB routing as described here [1] to get internet via GPRS for my laptop.
Now I would like to do the same via wifi instead usb cable.

[1] http://wiki.maemo.org/N900_USB_router