'make' w/ latest 1.5-branch (1.5.27a) fails @ "X--tag=CC: command not found"

[snowcrash+libtool]

hi,

i've

 glibtool --version
  ltmain.sh (GNU libtool) 1.5.27a (1.1220.2.497 2008/02/14 23:48:55)

installed on

 uname -v
  Darwin Kernel Version 9.2.0: Tue Feb  5 16:15:19 PST 2008;
root:xnu-1228.3.13~1/RELEASE_PPC

atm, i'm building latest IDN,

 ftp://alpha.gnu.org/pub/gnu/libidn/libidn-1.5.tar.gz

from src. out of the box,

 ./configure
 make

completes without error. but, if i first,

 glibtoolize -f -c
 autoreconf -f -i

then again,

 ./configure
 make

it dies @,

   ...
   mv unistd.h-t unistd.h
   make  all-am
   /bin/sh ../libtool --tag=CC   --mode=compile gcc -std=gnu99
-DHAVE_CONFIG_H -I. -I..   -I/usr/local/include  -g -O2 -MT
progname.lo -MD -MP -MF .deps/progname.Tpo -c -o progname.lo
progname.c
   ../libtool: line 821: X--tag=CC: command not found
   ../libtool: line 854: libtool: ignoring unknown tag : command not found
   ../libtool: line 821: X--mode=compile: command not found
   ../libtool: line 988: *** Warning: inferring the mode of operation
is deprecated.: command not found
   ../libtool: line 989: *** Future versions of Libtool will require
--mode=MODE be specified.: command not found
   ../libtool: line 1132: Xgcc: command not found
   ../libtool: line 1132: X-std=gnu99: command not found
   ../libtool: line 1132: X-DHAVE_CONFIG_H: command not found
   ../libtool: line 1132: X-I.: command not found
   ../libtool: line 1132: X-I..: command not found
   ../libtool: line 1132: X-I/usr/local/include: No such file or directory
   ../libtool: line 1132: X-g: command not found
   ../libtool: line 1132: X-O2: command not found
   ../libtool: line 1132: X-MT: command not found
   ../libtool: line 1132: Xprogname.lo: command not found
   ../libtool: line 1132: X-MD: command not found
   ../libtool: line 1132: X-MP: command not found
   ../libtool: line 1132: X-MF: command not found
   ../libtool: line 1132: X.deps/progname.Tpo: No such file or directory
   ../libtool: line 1132: X-c: command not found
   ../libtool: line 1185: Xprogname.lo: command not found
   ../libtool: line 1190: libtool: compile: cannot determine name of
library object from `': command not found
   make[3]: *** [progname.lo] Error 1
   make[2]: *** [all] Error 2
   make[1]: *** [all-recursive] Error 1
   make: *** [all] Error 2

searching on ("X--tag=CC: command not found"), there's _one_ recent
(Feb 5 '08) result. Tho my italian's not so good ;-) seems like a
libtool bug suspect.

is it?  any workaround atm?

thanks.