I'm using the Facebook app RSS Grafitti to post my blog posts on Facebook. However, none of them appear, because they can't find a pubdate. I've seen some articles here, but they only apply to WP ver. 2, so I don't want to risk messing anything up by adding ver. 2 codes. I'm a PHP and WP newbie.
How can I get the pubdate into my RSS feed? What files to edit and what to write? If it's relevant, I'm using the Black on White (serif) 1.2 theme.