Hi mate,
Australia and New Zealand are further from the UK than Christmas Island.
Christmas Island is a 3 hour flight from Honolulu, one flight in per week on a Tuesday. Flights from Honolulu to Christmas Island are £300 return and UK to Honolulu vary between £400-700 depending on when you fly. Flights for the week of 22nd July are approximately £600.
An overnight stay on the outbound leg is required in Honolulu to connect the next morning to Christmas Island.
We will also be running a 2 week hosted trip in February 2009 (3rd-17th) so this might be the one for you. Same price.
Regards
Mat