Hi, now I use ezpublish 5.4 i found many user with same login and email ?
Yes… what is your question?
One user can have login == email. This is not a problem at all.
Several users can have the same login as each other, this can happen especially if you have upgraded an older site, as older versions were not strict on this when registering. This is not a problem on login, because both the login and the password is checked.
But you should be careful when using the API to fetch users by login, like: eZUser::fetchByLogin()
It is safer to fetch by ID, which is always unique.