I think I found a solution (at least it worked perfectly for me, and it makes some sense).
Let me tell you first the scenario I had:
- WordPress 2.1, fresh install
- K2 theme (0.9.5 RC1)
- Server: Win2003 / IIS 6 / PHP 5.2.1 / MySQL 5.0.22
The problem I had: When deleting a post from the Admin > Manage section, the entry disappeared but after a refresh, the post was still there.
I noticed that this only happened when K2 was active, so I traced the problem deep down to the file prototype.js, which wasn't being loaded from the core WP files if K2 was selected.
It would be wise to backup the files involved, just in case something goes wrong.
So, open the file
wp-content/themes/k2/js/prototype.js.php and delete everything except for the first php tag (the one that looks something like
// check to see if the user has enabled
... some more code here (about 15 lines)...
Now, copy the entire contents of
wp-includes/js/prototype.js to the end of your recently modified prototype.js.php file. Now save/put the file back on the server.
Now, go to the admin > manage posts area, clear your browser's cache (or press CTRL+F5 on Internet Explorer, so you force a complete refresh). The delete buttons should be working now (worked for me).