I have successfully used xlibs to build a variety of pkgsrc.

x11/qt3-lib has failed to build because:

...
fplusstyle.lo .obj/release-shared-mt/moc_qplatinumstyle.lo
.obj/release-shared-mt/moc_qsgistyle.lo
.obj/release-shared-mt/moc_qwindowsstyle.lo
.obj/release-shared-mt/moc_qmotifstyle.lo  -L/usr/lib -L/usr/lib
-L/usr/lib -lpng -lz -lGL -lXmu -lXrender -lXft -lfreetype -lfontconfig
-lXext -lX11 -lm -lICE -lSM -lpthread -rpath  /usr/qt3/lib
*** [buildlink2] Warning: libtool detected
-L/scratch/pkgsrc/x11/qt3-libs/work.puget/qt-x11-free-3.2.3/lib
mkdir ../lib/.libs
grep: //scratch/pkgsrc/x11/qt3-libs/work.puget/.buildlink/lib/libX11.la:
No such file or directory

I don't have any .buildlink/lib/libX11.la.

My work directory  has
/scratch/pkgsrc/x11/qt3-libs/work.puget/.buildlink/.libX11_buildlink_done
which contains:

/include/X11/ImUtil.h: not found
/include/X11/XKBlib.h: not found
/include/X11/Xcms.h: not found
/include/X11/Xlib.h: not found
/include/X11/Xlibint.h: not found
/include/X11/Xlocale.h: not found
/include/X11/Xresource.h: not found
/include/X11/Xutil.h: not found
/include/X11/cursorfont.h: not found
/include/X11/region.h: not found
/lib/libX11.*: not found

Hmmm... somewhere my /usr (LOCALBASE) is being chopped off.

I will have to look closer. Something has changed for me lately. ...

   Jeremy C. Reed
   http://www.reedmedia.net/