I'm in a claim based installation of sharepoint 2010. My users are matched by user GUID in this form:
My GUID is case sensitive.
If I use SPEnsureUser(provider|GUID@mydomain.dom) it creates the user but with lowercase login name!
I tried AddUser(provider|GUID@mydomain.dom, mail, name, note) but the user has a lowercase login name.
With SPFarm.local.MigrateUser( lower --> normal case) the login name comes as I want it.
There is any other way to create new user on sharepoint?