Thanks esmi for your help. I reset the plugins folder, the error was caused by MyGallery plugin. However the plugin couldn’t be activated because it was missing files streams.php and gettext.php in the wp-includes folder.
Checked now the freshly downloaded 2.9.2 version, and these files are surely missing. Isn’t it strange?
seans9er, did you figure out what was wrong? I have the same problem now, check http://vicki.sk, and I see your theme is working fine now.
