Mike’s right, Stuart. You could also make up your own adapter cable. I did that using plugs and sockets I got from Model Power (http://www.modelpower.co.uk) they do 5 Futaba or JR plugs or sockets for £1.95 plus p&p.
Fleet used a different wiring convention for their plugs/sockets to other manufacturers: red/black/white; Futaba and Graupner/JR use black/red/white so beware. It is possible to connect Futaba or JR type plugs to Fleet sockets but not vice-versa without shaving the lugs off the Fleet plugs, so you can make up a cable with a Futaba plug wired as Fleet at one end and a Futaba socket at the other wired as Mr Futaba intended.
Hope that helps.
Ian