You have not properly upgraded your site. Please read the upgrade documentation as per our announcement which is located under the documentations folder of the downloaded code.
It appears to me you have not installed any of the vbulletin 4 plugins which is part of an install or upgrade.
IMPORTANT - FOR VBULLETIN 4 ONLY. New plugins included in download.
In the install directory set permissions on the file product_class.xml, source-vb4.xml and source-vb42.xml files to 777
2. Go to your classifieds admin panel ( http://www.yoursite.com/classifieds/adm-index.php ) and hit the option to generate vbulletin plugin xml. That file will download to your computer.
3. Go into your vbulletin admin panel and under plugins & products select the option to manage products. You can then use the add/import product option
and upload the xml file you downloaded to your computer called product_class.xml file. Once that is done your forum will show gallery content.
4. Thats it your done!!