www/htdig-devel fails to build on Solaris

[segv%netctl.net@localhost]

This problem occurs when building the package on Solaris with GCC. When pkgsrc
compiler is set to SunPro the build goes fine past this stage, but fails later.
Anyway, I'm trying to build it with GCC, but something is wrong with libtool.
Can anyone suggest where the problem might be?

===> Building for htdig-3.2.0b6
Making all in db
/opt/pkg/bin/bmake  all-am
/bin/ksh ./libtool --mode=compile gcc -DHAVE_CONFIG_H -I. -I. -I.
-I./../htlib  -D_REENTRANT -I/opt/pkg/include  -O3 -mcpu=ultrasparc -mvis
-mv8plus -pipe -I/opt/pkg/include -c -o bt_compare.lo `test -f 'bt_compare.c'
|| echo './'`bt_compare.c
libtool: compile: unable to infer tagged configuration
libtool: compile: specify a tag with `--tag'
*** Error code 1

Stop.
bmake: stopped in /opt/pkg.obj/www/htdig-devel/work.e450-lan/htdig-3.2.0b6/db
*** Error code 1