For an example of incorrect url, see:
http://ez.no/developer/forum/install_configuration/ezpublish_4_0beta_cannot_login_with_administration_interface
EZP-12134 Log in to the eZ Publish Administration Interface does not work from ezwebin
EZP-12162 HostMatchMapItems is not set correctly after installation
EZP-13886 Problem with kickstart.ini and AdditionalLoginFormActionURL