Vista ICS doesn't work

[guest]

- I set up two networks in my house. One is LAN 192.168.0.0/25 the other is
WLAN 192.168.0.128/25. One of the computers (the only one with Vista) is
connected to both of them and is connected to internet using ADSL modem
connected to USB. Thing is I want to share internet connection with both of
those networks. When I was using Win XP I simply used ICS to share it on LAN
and manually set IP address, default gateway and DNS server address an all
computers using my WLAN network. Everything was working fine. Now there is a
problem. I've tried doing the same in Vista. ICS is working OK but no
computer is able connect to the internet using WLAN. When I ping something
in the internet using WLAN network there is no answer. Computers in both
networks see each other. An obvious solution is creation of network bridge
but I don't want to do it. Vista seems to be blocking something and I don't
know what.

Computer 1 (Vista) Internet connection is ok:
LAN (ICS Host)
IP address: 192.168.0.1
subnet mask: 255.255.255.128

WLAN
IP address: 192.168.0.129
subnet mask: 255.255.255.128

Computer 2 (XP) Internet connection is ok:
LAN (ICS Client)
IP address: 192.168.0.2
subnet mask: 255.255.255.128
gateway: 192.168.0.1

Computer 3 (XP) No internet connection:
WLAN
IP address: 192.168.0.132
subnet mask: 255.255.255.128
gateway: 192.168.0.129

When there was Win XP on Computer 1 all I had to do was manualy seting up IP
address of DNS server on Computer 3 and I had internet connetion there. Now
it is no longer working. Why? I know I could set up a network bridge on
Computer 1 but I don't want to.

I can ping both Computer 1 and Computer 2 from Computer 3 but when I'm
trying to ping something in the internet there is no answer.

- Make both network use slash 24 meaning 255.255.255.0. Also use 192.168.0.1 as WLAN IP on Vista.