Here is the patch that I ended checkin in...

2009-01-13  Mark Kettenis  <kettenis@gnu.org>

        * utils.c (host_address_to_string): Reimplement in a way that
        avoids the cast of the address to long.

Tested on x86-linux and x86-windows.  I also re-built the debugger
on Vista64, and used "set debug arch" to verify that it can print
host addresses.

-- 
Joel