subscription-manager for RHEL 5.6

Hello...

I have a handful of RHEL 5.6 machines that (for whatever reason) were not originally registered using rhn_register. I did not realize this until a couple of weeks ago.

Now that RHN Classic has been retired, I am unable to get these systems registered. I can't migrate them from RHN Classic -> subscription manager because they aren't in RHN Classic, and I can't download the subscription manager repos because they're not registered.

I have a support case open, but I thought this might be a quicker path to resolution. HOpefully, somebody has come across this issue before! A google and knowledgebase search didn't help me much.

So frustrating - help!