Auto delete comments in que after XX days?

I use the Comment Authorization plugin from Skippy.net, and I love it. However, there are times when people don’t complete the authorization process and the comments sit in the moderation que until I go clear them out (along with the spam).

My goal is to never have to look in the que again. I was wondering if anyone knows of (or could create) a plugin that automatically deletes comments from the moderation que that are older than XX days. This would also have the added benefit of clearing out the spam as well.