From the BBC:
Microbes locked in Antarctic ice for as much as eight million years have been “resuscitated” in a laboratory.
Researchers melted five samples of ice from the debris-covered glaciers of Antarctica which range in age from 100,000 years to eight million years.
When given nutrients and warmth, the microbes resumed their activity – although younger microorganisms grew more successfully than the older ones.
According to the news story, the paper is published in the Proceedings of the National Academy of Sciences, but I couldn’t find it at the time of writing.
Update: the full text of the paper is now available.