You need to have the fastboot files in the same directory as the recovery image. If you are on windows that means the fastboot.exe and associated dll which are available from hashcode's site.
Edit: just saw you figured it out, disregard :P
Sent from my DROID RAZR HD using xda app-developers app
Last edited by ikesik; 9th April 2013 at 04:39 PM.