I have been having this issue since the 3.0 release. I update to the latest version, and the dashboard displays that I am running version 3.04 and yet the yellow bar that notifies about the availability of a new version and the need to update still appears.
If I hit the "Update Now" button, I am taken to the update page which shows:
You have the latest version of WordPress.
You have the latest version of WordPress. You do not need to update. However, if you want to re-install version 3.0.4, you can do so automatically or download the package and re-install manually:
This occurs on 3 blogs of mine, all using an official Arabic - localized version of WP by ar-wp.com. However, I am using Native Dashboard plugin to display the dashboard in English. Dont know if this is what causes the problem, just mentioned it.
What is wrong?