I don't believe Debian compiles libc.so with -fomit-frame-pointer (Joel, please correct me if I'm wrong). The point of the _g libraries IMO is to be able to get a backtrace with arguments, which is often more useful than a bare backtrace.
However, the _g libraries are static, and thus wouldn't provide that unless the program was explicitly linked with -lc_g.
-- Joel Klecker (aka Espy) <URL:http://web.espy.org/> <URL:mailto:jk@espy.org> <URL:mailto:espy@debian.org> Debian GNU/Linux PowerPC -- <URL:http://www.debian.org/ports/powerpc/>