Cannot register servers to RHN

Yesterday I spawned 2 virtual servers, both using Redhat 6.2 x64.

The RHN Registration tool isnt working for either server, and I cannot figure out what's wrong.

1) I launch the RHN Registration tool
2) I select the first option
'I would like to receive updates from RedHat network (I don't have access to Redhat network sattelite or proxy)'

3) I enter the corporate account information into the login box and continue
4) I select the 'limited updates' and continue
5) I ensure my system name is ok, select to send both hardware and package profile and click forward

6) I am then immediately presented with a 'Problem registering system' message.

See attached for further clarification. Can anybody help??

Thanks,
James