Ok. I just noticed that 8.0 is posted so I can be a bit more specific.
In 8.0 we made some changes to Swift to make it more like a standard Swift server. We now require a specific Swift account for users to access the cluster via Swift. That account can be associated with a regular account for file permission purposes, but just turning on Swift no longer means that just anyone can access it via Swift.
We also changed where Swift account live. There is a specific path (something like /ifs/lwSwift or something like that, I'd have to look it up). Prior to 8.0, we just used user home directories which had to be defined.