I got some serious problems when trying to import an exported ZClass. I have enhanced a ZClass by editing some part of the propertysheets and moving around some methods. I though that the most straight way was to import the ZClass from my development server to the production server. - But when I tried to edit an previously created object depending on my ZClass, I get the old behaviour of my ZClass. - When I tried to restart the production server, I got corrupted data in the products folder. I gave it up and restored my backup. Today, I have tried to make a distribution package and I put it in the lib/python/products folder of my production server. I deleted the previous version of my ZClass through the Control Panel and I restarted Zope. And then everything goes right. So, is it definitly better to work with distribution package of ZClass instead of importing the same ZClass?