sudo port -v install worker +universal
--->  Computing dependencies for worker.
--->  Configuring worker
checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for gawk... gawk
checking whether make sets $(MAKE)... yes
checking whether to enable maintainer-specific portions of Makefiles... no
checking for gcc... /usr/bin/gcc-4.2
checking for C compiler default output file name... a.out
checking whether the C compiler works... yes
checking whether we are cross compiling... no
checking for suffix of executables... 
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether /usr/bin/gcc-4.2 accepts -g... yes
checking for /usr/bin/gcc-4.2 option to accept ISO C89... none needed
checking for style of include used by make... GNU
checking dependency style of /usr/bin/gcc-4.2... none
checking whether we are using the GNU C++ compiler... yes
checking whether /usr/bin/g++-4.2 accepts -g... yes
checking dependency style of /usr/bin/g++-4.2... none
checking for a BSD-compatible install... /usr/bin/install -c
checking for ranlib... ranlib
checking for gawk... (cached) gawk
checking how to run the C++ preprocessor... /usr/bin/g++-4.2 -E
checking for X... no
configure: error: X Window libraries and headers not found!
*********************************************************************
* Check your X installation (many distributions have these files in *
* the ...devel-packages (e.g. xdevel)).                             *
*********************************************************************
Error: Target org.macports.configure returned: configure failure: shell command " cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_x11_worker/work/worker-2.17.4" && ./configure --prefix=/opt/local --disable-dependency-tracking " returned error 1
Command output: checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for gawk... gawk
checking whether make sets $(MAKE)... yes
checking whether to enable maintainer-specific portions of Makefiles... no
checking for gcc... /usr/bin/gcc-4.2
checking for C compiler default output file name... a.out
checking whether the C compiler works... yes
checking whether we are cross compiling... no
checking for suffix of executables... 
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether /usr/bin/gcc-4.2 accepts -g... yes
checking for /usr/bin/gcc-4.2 option to accept ISO C89... none needed
checking for style of include used by make... GNU
checking dependency style of /usr/bin/gcc-4.2... none
checking whether we are using the GNU C++ compiler... yes
checking whether /usr/bin/g++-4.2 accepts -g... yes
checking dependency style of /usr/bin/g++-4.2... none
checking for a BSD-compatible install... /usr/bin/install -c
checking for ranlib... ranlib
checking for gawk... (cached) gawk
checking how to run the C++ preprocessor... /usr/bin/g++-4.2 -E
checking for X... no
configure: error: X Window libraries and headers not found!
*********************************************************************
* Check your X installation (many distributions have these files in *
* the ...devel-packages (e.g. xdevel)).                             *
*********************************************************************

Warning: the following items did not execute (for worker): org.macports.activate org.macports.configure org.macports.build org.macports.destroot org.macports.install