From some time Vista started giving me very strange problem with ICS. After turning computer on and booting system there is internet on my machine, but there is nothing on second one. Second machine (XP Pro) notices that internet is shared (in Network connections there is icon showing "Local connection 2 on -_-") but in fact there is none.

DHCP is working (second computer receives IP) and ping between computers works correctly. From what I saw DNS is not a problem here (tried connecting to some site by their IPs and nothing). It's not a major bug, because after disabling and reenabling ICS everything is working as it should, but it is very irritating when I'm in a middle of a game, and someone is telling me they don't have internet...
Anyone had problem like this?