Creating CDC system table on SQL Server 2008
As the very article you linked says:


  You can script those objects from a new dummy database in which you
  have successfully enabled CDC


These tables are not 'system' as in 'they belong to the sys namespace and protected from direct user operations' but are 'system' as in 'they are absolutely ordinary tables used by stored procedures shipped with CDC and MS just wishes nobody would mess with them'...