aminura 0 Light Poster

Hey!
Recently my wireless router stopped working due to some electrical trouble with it.So for the time being I was trying out ad hoc networking(My knowledge about this is really meager).My desktop has Linksys wireless G PCI adapter and my laptop is centrino..both having win xp as operating systems.
I went through some websites and was able to configure an ad hoc wireless network on desktop and gave it IP -- 192.168.100.1 and my laptop 192.168.100.2 ,both are able to ping each other.Despite of enabling internet sharing on the computer which is connected to ethernet cable, I am not able to get internet on laptop.. :?:
I would appreciatiate if somebody could help me with this....Thanks