On the wine-users list, we're getting a lot of users who have old or even ancient .wine directories, and whose problems go away with a fresh .wine directory
Perhaps we should have wineprefixcreate stamp the version of wine the .wine directory was created with, make wine-1.0 refuse to run with pre-1.0 .wine directories, and require that future versions of wine run properly with .wine directories created by any earlier stable release of wine.
It wouldn't be hard, at least at first, and it might save a lot of support inquiries. What say?