I gave up on some library-related pkgsrc problems and decided to 
rebuild all of my packages from scratch.  I cleaned out /usr/pkg and
/var/db/pkg and tried to recompile everyting from up-to-date pkgsrc.  (This 
is on a 1.6.1 i386.)  But a number of programs unable to build because 
they can't find -liconv.  The libiconv was installed successfully, and 
many other packages found it successfully:

s132$ pkg_info libiconv         
Information for libiconv-1.9.1nb1:

Comment:
Character set conversion library

Required by:
gettext-lib-0.11.5nb2
gettext-0.11.5nb3
madplay-0.15.0bnb1
mad-0.15.0b
glib2-2.2.3nb1
atk-1.2.4
libxml2-2.5.10nb1
libwmf-0.2.8nb3
everybuddy-0.2.0nb4
pilot-link-libs-0.11.7nb1
pango-1.2.5
gtk2+-2.2.4
linc-1.0.1nb2
wv-0.7.6nb1
libIDL-0.8.0nb2
ORBit2-2.6.0nb3
aumix-2.8nb2
GConf2-2.2.0nb2
libxslt-1.0.32
libglade-0.17nb4
scrollkeeper-0.3.12nb2
bonobo-activation-2.1.1nb2
libbonobo-2.2.0nb3
gnome-vfs2-2.2.4nb3
gnome-vfs-1.0.5nb3
xmms-1.2.7nb9
libgnome-2.2.3nb2

But here's what happened when I tried to build gdk-pixbuf-gnome:

/bin/sh ../libtool --mode=link cc  -O2 -I/usr/pkg/include -I/usr/X11R6/include -L/usr/pkg/lib -Wl,-R/usr/pkg/lib -L/usr/X11R6/lib -Wl,-R/usr/X11R6/lib -o test-gdk-pixbuf  test-gdk-pixbuf.o libgdk_pixbuf.la -L/usr/pkg/lib -Wl,-R/usr/pkg/lib -lgmodule -lglib -L/usr/X11R6/lib -Wl,-R/usr/X11R6/lib -Wl,-R/usr/X11R6/lib -L/usr/X11R6/lib -L/usr/X11R6/lib -lgtk -lgdk -L/usr/pkg/lib -Wl,-R/usr/pkg/lib -lgmodule -lglib -lintl -lXi -lXext -lX11 -lm -ltiff -ljpeg -lpng -lz -L/usr/X11R6/lib -Wl,-R/usr/X11R6/lib -L/usr/pkg/lib -Wl,-R/usr/pkg/lib -lgnomeui -lart_lgpl -lgdk_imlib -lSM -lICE -lgtk -lgdk -lgmodule -lXi -lXext -lX11 -lgnome -lgnomesupport -lesd -lossaudio -laudiofile -lm -lglib -lintl -lgmodule -lintl
cc -O2 -I/usr/pkgsrc/graphics/gdk-pixbuf-gnome/work/.buildlink/include -I/usr/pkgsrc/graphics/gdk-pixbuf-gnome/work/.buildlink-x11/include -Wl,-R/usr/pkg/lib -Wl,-R/usr/X11R6/lib -o .libs/test-gdk-pixbuf test-gdk-pixbuf.o -Wl,-R/usr/pkg/lib -Wl,-R/usr/X11R6/lib -Wl,-R/usr/X11R6/lib -Wl,-R/usr/pkg/lib -Wl,-R/usr/X11R6/lib -Wl,-R/usr/pkg/lib  -L/usr/pkgsrc/graphics/gdk-pixbuf-gnome/work/.buildlink/lib -L/usr/pkgsrc/graphics/gdk-pixbuf-gnome/work/.buildlink-x11/lib ./.libs/libgdk_pixbuf.so -L/usr/pkg/lib -L/usr/X11R6/lib /usr/pkg/lib/libtiff.so /usr/pkg/lib/libjpeg.so /usr/pkg/lib/libpng.so /usr/lib/libz.so /usr/X11R6/lib/libgnomeui.so /usr/X11R6/lib/libart_lgpl.so /usr/X11R6/lib/libgdk_imlib.so -lSM -lICE /usr/X11R6/lib/libgtk.so /usr/X11R6/lib/libgdk.so -lintl -lXi -lXext -lX11 /usr/X11R6/lib/libgnome.so /usr/X11R6/lib/libgnomesupport.so -lz -liconv -lc /usr/pkg/lib/libesd.so -lossaudio /usr/pkg/lib/libaudiofile.so -lm /usr/pkg/lib/libglib.so /usr/pkg/lib/libgmodule.so /usr/l!
ib/libintl.so -Wl,--rpath -Wl,/usr/X11R6/lib -Wl,--rpath -Wl,/usr/pkg/lib
/usr/bin/ld: cannot find -liconv
collect2: ld returned 1 exit status
gmake[3]: *** [test-gdk-pixbuf] Error 1
gmake[3]: Leaving directory `/usr/pkgsrc/graphics/gdk-pixbuf-gnome/work/gdk-pixbuf-0.22.0/gdk-pixbuf'
gmake[2]: *** [all-recursive] Error 1
gmake[2]: Leaving directory `/usr/pkgsrc/graphics/gdk-pixbuf-gnome/work/gdk-pixbuf-0.22.0/gdk-pixbuf'
gmake[1]: *** [all-recursive] Error 1
gmake[1]: Leaving directory `/usr/pkgsrc/graphics/gdk-pixbuf-gnome/work/gdk-pixbuf-0.22.0'
gmake: *** [all-recursive-am] Error 2
*** Error code 2

Stop.
make: stopped in /usr/pkgsrc/graphics/gdk-pixbuf-gnome
*** Error code 1

Stop.
make: stopped in /usr/pkgsrc/graphics/gdk-pixbuf-gnome


		--Steve Bellovin, http://www.research.att.com/~smb