Automator Action

Create new Entourage Message with Bcc

Optional: Place this script in the Applescript action if you want the window to be moved out of the top left corner.

tell application "Microsoft Entourage"
  set theWindows to every window whose class is draft window
  repeat with aWindow in theWindows
   set position of aWindow to {75, 140}
  end repeat
 end tell

Save as Workflow and place in the Entourage Script Menu I Items folder. Add a shortcut. Check out the Sample Automator Workflows in the folder.

How to add shortcuts to a script