Cisco Wireless :: WAP4410N Set Up 3 Story Wi-Fi Network

I have 4 WAP4410N sitting here to set up a 3 story Wi-Fi network. Since the WAP4410N is advertised as being able to work as a WDS repeater, I thought this might be a good product to allow users (only a handful of clients, around 4 or 5 at a time) to roam the building. To keep matters simple, I first tried to deploy only two APs:
 
I have deployed one WAP4410N as AP in a central location, and I'm actually very happy with the area it covers all by itself.The first AP (Version: 2.0. 3. 3) is configured as follows:

- Static IP, connected to wired network
- AP Mode: Access Point, allow wireless signal to be repeated by: wireless MAC of second WAP4410
- B/G/N Mixed, Channel 6, one SSID
- WPA-Personal with TKIP, Isolation is off
 
This configuration did not work. Clients could associate with both AP's, but when connected to the repeater, no packets are routed, thus no IP via DHCP etc. Funny enough, about once per 20-25 reboots, traffic was routed just fine, and the test client was actually roaming from one AP to the other for a few minutes - but the magic was gone after the next AP reboot.I spent the weekend (need time slots when nobody is working ...) trying just about every possible configuration to get this to work:
 
- Different channels
- Other WPA security (we cannot go WEP or unencrypted)
- Wired MAC address instead of wireless one
- Different wireless network modes (B, G, N) ...