I thought that wasn't possible?
There is a time period where URLs can not be reposted. Once that time has expired they can be posted again.
As Abraham mentioned, there's a timeout for duplicate detection.
In this case, it's probably worthwhile. I remembered the post from a year ago, and it's much more polished a year later, and is likely to get a better reception.
http://www.hnsearch.com/search#request/all&q=http%3A%2F%...