The New Zealand market was particularly slow, and these deals - about a 50 per cent discount - were only for New Zealand residents, he said.
The cheapest package on the Rhapsody of the Seas is $1500, which includes two quarterfinals tickets in Wellington worth $800. The remaining $700 pays for eight nights of accommodation, meals, entertainment and a trip around the North Island, stopping at Wellington, Napier, Tauranga and the Bay of Islands. The trip leaves from and returns to Auckland.
"We're finding that half the people booking now are interested in the cruise first and rugby second," Mr Kirwan said.
An industry source said other ships arriving in New Zealand for the tournament were also struggling to fill.
The tournament is expected to draw as many as 85,000 international visitors to New Zealand, but hotel operators and government agencies have warned the hype of a packed country for six weeks was a myth.
"We need to extinguish the perception that the whole country will be full throughout RWC 2011," a report by the Ministry of Economic Development's tourism research arm says.
Visitor arrivals to New Zealand during the Cup are projected to be at most 9000 a day.