It has been introduced between 0.6b and 0.7.1, in 0.6b was used in ec_main
  	2008-03-19 18:49:08 CET 	Obsolete 	Hoary 	release 	universe 	net 	1:0.7.1-1
  	2008-01-09 19:47:02 CET 	Obsolete 	Warty 	release 	universe 	net 	1:0.6.b-2