N2179 exception_ptr, interest?

[Peter Dimov]

Two Boost contributors, Frank Mori Hess and Sebastian Redl, have produced 
"almost functional" proof of concept implementations of N2179 (copying and 
rethrowing exceptions) for g++. See for example:

http://lists.boost.org/Archives/boost/2008/04/136130.php
http://lists.boost.org/Archives/boost/2008/04/136380.php
http://lists.boost.org/Archives/boost/2008/05/136865.php

and the associated threads.

Is there interest in their work? What can be done to move this forward so 
that we can see std::exception_ptr in 4.4 or 4.5?