Since recently on one of my sites a strange problem is happening. When a new page is created, the guid is not correctly saved in the database. So say I create a page with the title "The new page". I save it. Using pretty urls the page should be located at:
example.com/the-new-page
however if I look in the database (with phpmyadmin) the guid field is:
http://example.com
which should be
http://example.com/the-new-page
This is only happening recently. I'm running 3.01 and everything else seems to be fine.