Desktop login failing

I`m struggling with a bad adsl connection latelty. So bad that my connection often dies for hours, It's supposed to be my internal telephone line which I've replaced by now so I`m hoping for the best.

Anyway .. we had short power outage yesterday night and my iMac (running ubuntu) got rebooted. When trying to log in, the screen went brown and nothing else happened.
Strange.. didn't see any errors in the logs , when switching to console mode one error catched my eye, some files couldn't be untarred because they were in the future.
While looking at the permissions of files in /tmp where gnome etc tend to throw some files , I noticed that a lot of files were dated 1 january 1904 (yes that's right 1904 !!).
Which meant that ntpdate had failed, it couldn't look up the hostname for it's ntp server (in this case because I had no ip connectivity).

So because a DNS lookup failed I could not log on to my desktop..