I don't know if this is a false positive but running ./autogen.sh on Mac OS X 10.5/Intel with Fink loaded in the environment tells me that /usr/bin/libtool is the LIBTOOL. On Mac OS X, /usr/bin/libtool is a totally different program, /usr/bin/glibtool is the one ./autogen.sh wants.

pd@macosx105-i386 Gem $ ./autogen.sh && ./configure && make -j4 PATH: /sw/bin:/sw/sbin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/X11/bin:/usr/X11R6/bin AUTORECONF: /sw/bin/autoreconf AUTOHEADER: /sw/bin/autoheader AUTOMAKE : /sw/bin/automake ACLOCAL : /sw/bin/aclocal LIBTOOL : /usr/bin/libtool LIBTOOLIZE: /sw/bin/libtoolize AUTOCONF : /sw/bin/autoconf running autoreconf

FYI, this is the build machine, it has libtool2 2.4.2-1 installed via Fink, so I suppose ./autogen.sh should find /sw/bin/libtool.

.hc