Calendar Plugin Help Needed

Noobie to WP and have been plugging along and learning things reasonably well on my own so far. I am wondering if someone can help me with this, I have found a calendar here and would like to know what plugin it is. It is exactly what I am looking for on a website I am doing for a friend. Also will it work in 3.1.2? if not are there any other suggestions, I need to have each date hi-lighted when there is an event and taken to the info about it and to have comments enabled is a huge bonus. Also love the fact that it keeps each date after the event has passed.

Cheers,
Brian