Username with blanks

Current Situation

When a ldap user have blanks in its name the authentication works. When the user should have roles assigned in the section [users] no roles are assigned

Desired Behaviour

It should be possible to specify a user in the section [users] with %20 as blanks. e.g. the user fritze mueller can be specified with fritze%20mueller. Doing this blanks can be used in the login screen or as a ldap user name. many blanks will be substituted to one %20.