The Collaborative International Dictionary of English v.0.48:

Sundowner \Sun"down`er\, n.
   A tramp or vagabond in the Australian bush; -- so called from
   his coming to sheep stations at sunset of ask for supper and
   a bed, when it is too late to work; -- called also traveler
   and swagman (but not all swagmen are sundowners).

         Sundowners, -- men who loaf about till sunset, and then
         come in with the demand for unrefusable rations.
                                                  --Francis
                                                  Adams.
   [Webster 1913 Suppl.]

The Collaborative International Dictionary of English v.0.48:

Swagman \Swag"man\, n.
   A bushman carrying a swag and traveling on foot; -- called
   also swagsman, swagger, and swaggie.
   [Webster 1913 Suppl.]

         Once a jolly swagman sat beside a billabong
         Under the shade of a coolibah tree.
         And he sang as he sat and watched his billy boiling,
         `Who'll come a-waltzing Matilda with me?' --[Waltzing
                                                  Matilda, an
                                                  Australian
                                                  tune.]
   [PJC]

WordNet (r) 3.0 (2006):

swagman
    n 1: an itinerant Australian laborer who carries his personal
         belongings in a bundle as he travels around in search of
         work [syn: swagman, swagger, swaggie]

Moby Thesaurus II by Grady Ward, 1.0:

77 Moby Thesaurus words for "swagman":
   Arab, Bowery bum, beach bum, beachcomber, beggar, beggarly fellow,
   blighter, bo, budmash, bum, bummer, caitiff, derelict, devil,
   dogie, drifter, drunkard, fence, floater, gamin, gamine,
   good-for-naught, good-for-nothing, guttersnipe, hobo,
   homeless waif, human wreck, idler, landloper, lazzarone, loafer,
   losel, lowlife, mauvais sujet, mean wretch, mucker, mudlark,
   no-good, pauvre diable, piker, pilgarlic, poor creature,
   poor devil, ragamuffin, ragman, ragpicker, receiver, roadster,
   rounder, sad case, sad sack, shack, ski bum, skid-row bum, stiff,
   stray, street Arab, street urchin, sundowner, surf bum, swagsman,
   tatterdemalion, tennis bum, tramp, traveler, truant, turnpiker,
   urchin, vag, vagabond, vagrant, vaurien, waif, waifs and strays,
   wastrel, worthless fellow, wretch