Yes I think this is 'In Progress'. It may be enabled in a new install but I haven't tested that - Terry will know. It would need a migrate script for older installs.
ahhhh, on a clean install
[root@sme111 ~]# db yum_repositories show smecontribs
smecontribs=repository
EnableGroups=yes
GPGCheck=yes
MirrorList=https://mirrorlist.koozali.org/mirrorlist/smecontribs-10
Name=SME Server - contribs
Visible=yes
status=disabled
[root@sme111 ~]# db yum_repositories setprop smecontribs status enabled
[root@sme111 ~]# db yum_repositories show smecontribs
smecontribs=repository
EnableGroups=yes
GPGCheck=yes
MirrorList=https://mirrorlist.koozali.org/mirrorlist/smecontribs-10
Name=SME Server - contribs
Visible=yes
status=enabled