When 57-year-old IT specialist Denise Moloney first heard that for a payment of just $1750 she may qualify for a retirement pension from the UK government she suspected it was a scam.

Moloney, an Irish expat who moved to Australia in 1993, had worked in the UK between 1988 and 1993, during which time she paid National Insurance (a system of contributions paid by UK workers and employers) for five years.