Issue: After updating to WordPress 2.8, the custom field function does not seem to be working corerctly. After adding a custom field it would say that the custom field is updated however it does not appear in anywhere in your post.
Solution: No solution yet as of the moment. I am currrently checking on this and I’m hoping other users can comment as well for further inputs on solution or the cause of the problem.
Work Around: Go to edit posts and edit the post from their. You should then see you added custom field.