Hello Marc, If you Google cable release adaptors, Jessops in the U.K www.jessops.co.uk sell a Cable Adaptor Bracket and the German accessories maker Kaiser make a device that will do this, they both enable you to use ordinary Compur thread cable releases to push the button..
The electronic releases (MC-20 and MC-30), although expensive, givey ou the advantage of releasing the shutter without any physical movement of the camera. (Standard cable releases do impart a tiny bit of movement.) The MC-20 has a nice timer built-in which is great for longer exposures. Consider it to be a once-in-a-lifetime purchase.