[boost] can emacs cc-mode be made to do boost-style preprocessor indents?

From: Jonathan Graehl (boost_at_[hidden])
Date: 2004-09-30 17:52:13

The Boost style of nested indenting for preprocessor directives is 
nice.  I'm using cc-mode for emacs (the sourceforge version), and it 
doesn't seem to directly support this:

#if 1
# if 2
#  define A 1
# else
# endif
#endif

I found this cc-mode mailing list discussion that confirmed the lack of 
support: 
http://sourceforge.net/mailarchive/forum.php?thread_id=5382045&forum_id=6827

Anyone already got some working elisp for preprocessor autoindent?