I loaded the wireless extension using 'tce-load -i' and then 'iwconfig' and it detected my card as eth0. After I read something about requested firmware in 'dmesg', I decided to load the 'isl3886pci.tcz' as well and plugged my network card back in. Now 'iwconfig' says wlan0 and something about IEEE 802.11bg, Mode:Managed and a lot of stuff I can remember to be good.
I'm in a hurry now (wanna go to bed) so, didn't find a way to scan for networks and connect and see if that works but I guess we're on the way!
And if it will, can you then explain why all those drivers are included in one package, and I wasn't able to find how to make a package myself? Yes I know, there is a script in the package with driver-select, which comes close to what I want, but I'm just interested how this all is compiled and so.
EDIT: Oh I forgot to mention, that before I plugged my network card back in, I unloaded the 'prism54' driver so it's going to load again when I plugged the card back in. Maybe clear for you guys, but not for everyone I guess.