For which classes does your fetch works (you filter it on $classes) ? It seems that your fetch is trying to return objects that are carrying attributes calling for some custom datatypes that is not available anymore.
Could I suggest you to check your extensions, maybe one is missing from your /extension directory, or simply not activated (in /settings/override/site.ini.append.php).
It's really strange ...
Do you have tried to delete the attribute from your class and set it back ? The problem is ... it will certainly causes data loss if you have existing instances of this class :/
How do you have moved your content ? Using the export/import packages system, or with a mysql dump ?
