RSS entry wrong pubDate

Hey all. I’m looking at the RSS feed for one of my categories in Firefox with the URL: https://www.domain.com/category/category-name/feed/

The latest entry displayed has this date underneath the title:
Friday, June 04, 2010 1:25 AM

However, if I view source, this is what I find under it:
<pubDate>Thu, 03 Jun 2010 17:25:48 +0000</pubDate>

The problem with this is that I need the dates to be accurate because I’m parsing this RSS feed into other websites and the date is crucial. (The websites show the date of the latest entry to be June 3 not June 4.)

This is the lastBuildDate of the feed:
<lastBuildDate>Thu, 03 Jun 2010 17:25:48 +0000</lastBuildDate>

I have no cache plugins installed. Any idea what’s up with this situation?

Thanks for any help in advance!