[Plugin: WordPress Popular Posts] Old posts (older than 30 days0 keep showing up when I'm only

We’re having a problem with posts older than the sample period (30 days/month) showing up in our instances of WordPress Popular Post lists. We’re using this in a tabbed interface on our sidebar as Most Viewed (last 30 days) and Most Discussed (most comments in last 30 days).

It’s visible at this site, http://lakewood.advocatemag.com/ and most of the other five sites (listed as neighborhoods in the left sidebar)

Any ideas?

Kermit