Actually, this is not an error. The screen you have when viewing original articles is the override of the default node/view/full.tpl. The display is correct because override rules are defined in the override.ini file of the siteaccess and the match rules are probably set to match the "article" content class and of course not your newly copied class. You need to set correct override rules to solve this.
For more informations about override : http://ez.no/doc/ez_publish/technical_manual/3_6/reference/template_override_conditions
