There are new packages available for Mac OS/X (20110822 Snapshot)
Mountain Lion Users (10.8.x):
Download the DMG file, and read the README1ST file for information on
installing X11 on this platform. GNUBG will fail to run if X11 is not properly
Please read the README1ST file for installation requirements (X11), trouble shooting and miscellaneous help. If you experience random crashes in 3D mode on OS/X Lion 10.7, please see the README1ST file for a possible work around.
GNUBG must be installed to the /Applications folder.
If you need support for OS/X please contact Michael Petch at firstname.lastname@example.org