In their on-line blog, it stated the foursome were convicted last year under the untested Defence (Special Undertakings) Act of 1952.
Bryan Law of Cairns, Jim Dowling and Adele Goldie of Brisbane and Donna Mulhearn of Sydney will serve the short jail terms of between five days to two weeks.
The group said they were “very happy to take responsibility for our actions but we're not willing to contribute financially (and) will serve our prison time in lieu of that."
The Pine Gap Four entered the prohibited zone of the Pine Gap Joint Defence Facility on 9 December 2005 to conduct a Citizen's Inspection, with the intention of highlighting the base's - and Australia's - role in the Iraq war.
Previous incursions into the base resulted in charges of trespass, but then-Attorney-General Philip Ruddock created legal history by directing the DPP to charge the Four under the 1952 Act, carrying a sentence of up to seven years imprisonment.
The Pine Gap Four follow the non-violence philosophies of Jesus, Gandhi, Martin Luther King and Dorothy Day.
Their appeals against last year's convictions are due to commence on February 20.
Pine Gap Four Arrested (Pine Gap Four blogspot 13/02/08)
LINKS (not necessarily endorsed by Church Resources)
Pine Gap on Trial