Build of cups stops with linker errors:

Linking cupsd...
cc -L../cgi-bin -L../cups -L../filter -L../ppdc -L../scheduler -L/usr/local/lib/ -L/usr/local/lib -Wl,-R/usr/local/lib   -Wall -Wno-format-y2k -fPIC -Os -g -fstack-protector -o cupsd auth.o banners.o cert.o classes.o client.o conf.o dirsvc.o env.o main.o ipp.o listen.o job.o log.o network.o policy.o printers.o process.o quotas.o removefile.o select.o server.o statbuf.o subscriptions.o sysman.o -L. -lcupsmime \
		-lz -L/usr/local/lib -lgnutls    -lldap -lpam \
		-lpaper  -pthread -L/usr/local/lib -ldbus-1    -lcups -L/usr/local/lib -lgnutls    -pthread -lm -lcrypt  \
		 
client.o(.text+0x1daa): In function `encrypt_client':
/usr/ports/print/cups-base/work/cups-1.4.2/scheduler/client.c:3217: undefined reference to `_httpReadGNUTLS'
client.o(.text+0x1db9):/usr/ports/print/cups-base/work/cups-1.4.2/scheduler/client.c:3218: undefined reference to `_httpWriteGNUTLS'
gmake[1]: *** [cupsd] Error 1
gmake[1]: Leaving directory `/usr/ports/print/cups-base/work/cups-1.4.2/scheduler'
gmake: *** [all] Error 1
*** Error code 1

Stop in /usr/ports/print/cups-base.
*** Error code 1

        This error showed up in a search on a debian list,
        where the answer seemed to be to remove an out-of-date
        dependency.  I would have thought that portmaster would
        look after that, but I'm investigating...

Fix: 

Probably need to delete an obsolete library, but not
        sure how to find it.
How-To-Repeat: 	cd /usr/ports/print/cups; make