Testing dh24, specifically rhbz#841511 which claimed:

whenever I set ike to use DH24, I correctly see "calc_dh_shared(): time
elapsed (OAKLEY_GROUP_DH24)" on both initiator and responder, but there
is also incorrect "calc_dh_shared(): time elapsed (OAKLEY_GROUP_DH23)"
in the responder log... which is really confusing for me (nevertheless,
connection works fine).  this does not happen with dh22 or dh23

This test shows DH24 properly