Tried the release candidate on a new Ubuntu 13.04 (beta) system.  Installed the dependencies requested by bake.py check and bake.py show (for ns-3.17 configuration).

The build fails with this error:

 >> Building netanim-3.103 - Problem
   > Subprocess failed with error 2: ['make', '-j', '1']
 > Problem: Unmet dependency on module: netanim-3.103.
   Bake will continue since this module is not in the critical path. For more information call bake with -vv.

 >> Building ns-3.17 - Problem
   > Subprocess failed with error 1: ['/home/buildslave/scratch/ns-allinone-3.17.rc1/bake/source/ns-3.17/waf', 'configure', '--prefix=/home/buildslave/scratch/ns-allinone-3.17.rc1/bake/build', '--enable-examples', '--enable-tests']
 > Error:  Unmet critical dependency on module: ns-3.17 
   For more information call Bake with --debug and/or -vvv (bake --help)


The underlying problem is that gcc is present, but g++ is not.  Probably should check for "g++' in the list of required system dependencies (bake.py check)