> sudo port install GraphViz
Warning: port definitions are more than two weeks old, consider using selfupdate
--->  Fetching xorg-xtrans
--->  Attempting to fetch xtrans-1.2.6.tar.bz2 from http://ykf.ca.distfiles.macports.org/MacPorts/mpdistfiles/xorg-xtrans
--->  Verifying checksum(s) for xorg-xtrans
--->  Extracting xorg-xtrans
--->  Configuring xorg-xtrans
--->  Building xorg-xtrans
--->  Staging xorg-xtrans into destroot
--->  Installing xorg-xtrans @1.2.6_0
--->  Deactivating xorg-xtrans @1.2.5_0
--->  Cleaning xorg-xtrans
--->  Activating xorg-xtrans @1.2.6_0
--->  Cleaning xorg-xtrans
--->  Fetching xorg-xproto
--->  Attempting to fetch xproto-7.0.20.tar.bz2 from http://ykf.ca.distfiles.macports.org/MacPorts/mpdistfiles/xorg-xproto
--->  Verifying checksum(s) for xorg-xproto
--->  Extracting xorg-xproto
--->  Configuring xorg-xproto
--->  Building xorg-xproto
--->  Staging xorg-xproto into destroot
--->  Installing xorg-xproto @7.0.20_0
--->  Deactivating xorg-xproto @7.0.18_0
--->  Cleaning xorg-xproto
--->  Activating xorg-xproto @7.0.20_0
--->  Cleaning xorg-xproto
--->  Computing dependencies for xorg-libice
--->  Fetching xorg-libice
--->  Attempting to fetch libICE-1.0.7.tar.bz2 from http://ykf.ca.distfiles.macports.org/MacPorts/mpdistfiles/xorg-libice
--->  Verifying checksum(s) for xorg-libice
--->  Extracting xorg-libice
--->  Configuring xorg-libice
--->  Building xorg-libice
--->  Staging xorg-libice into destroot
--->  Computing dependencies for xorg-libice
--->  Installing xorg-libice @1.0.7_0
--->  Deactivating xorg-libice @1.0.6_0
--->  Cleaning xorg-libice
--->  Activating xorg-libice @1.0.7_0
--->  Cleaning xorg-libice
--->  Computing dependencies for xorg-libsm
--->  Fetching xorg-libsm
--->  Attempting to fetch libSM-1.2.0.tar.bz2 from http://ykf.ca.distfiles.macports.org/MacPorts/mpdistfiles/xorg-libsm
--->  Verifying checksum(s) for xorg-libsm
--->  Extracting xorg-libsm
--->  Configuring xorg-libsm
--->  Building xorg-libsm
--->  Staging xorg-libsm into destroot
--->  Computing dependencies for xorg-libsm
--->  Installing xorg-libsm @1.2.0_0
--->  Deactivating xorg-libsm @1.1.1_0
--->  Cleaning xorg-libsm
--->  Activating xorg-libsm @1.2.0_0
--->  Cleaning xorg-libsm
--->  Fetching xorg-util-macros
--->  Attempting to fetch util-macros-1.11.0.tar.bz2 from http://ykf.ca.distfiles.macports.org/MacPorts/mpdistfiles/xorg-util-macros
--->  Verifying checksum(s) for xorg-util-macros
--->  Extracting xorg-util-macros
--->  Configuring xorg-util-macros
--->  Building xorg-util-macros
--->  Staging xorg-util-macros into destroot
--->  Installing xorg-util-macros @1.11.0_0
--->  Deactivating xorg-util-macros @1.10.0_0
--->  Cleaning xorg-util-macros
--->  Activating xorg-util-macros @1.11.0_0
--->  Cleaning xorg-util-macros
--->  Fetching xorg-bigreqsproto
--->  Attempting to fetch bigreqsproto-1.1.1.tar.bz2 from http://ykf.ca.distfiles.macports.org/MacPorts/mpdistfiles/xorg-bigreqsproto
--->  Verifying checksum(s) for xorg-bigreqsproto
--->  Extracting xorg-bigreqsproto
--->  Configuring xorg-bigreqsproto
--->  Building xorg-bigreqsproto
--->  Staging xorg-bigreqsproto into destroot
--->  Installing xorg-bigreqsproto @1.1.1_0
--->  Deactivating xorg-bigreqsproto @1.1.0_0
--->  Cleaning xorg-bigreqsproto
--->  Activating xorg-bigreqsproto @1.1.1_0
--->  Cleaning xorg-bigreqsproto
--->  Fetching xorg-xcmiscproto
--->  Attempting to fetch xcmiscproto-1.2.1.tar.bz2 from http://ykf.ca.distfiles.macports.org/MacPorts/mpdistfiles/xorg-xcmiscproto
--->  Verifying checksum(s) for xorg-xcmiscproto
--->  Extracting xorg-xcmiscproto
--->  Configuring xorg-xcmiscproto
--->  Building xorg-xcmiscproto
--->  Staging xorg-xcmiscproto into destroot
--->  Installing xorg-xcmiscproto @1.2.1_0
--->  Deactivating xorg-xcmiscproto @1.2.0_0
--->  Cleaning xorg-xcmiscproto
--->  Activating xorg-xcmiscproto @1.2.1_0
--->  Cleaning xorg-xcmiscproto
--->  Fetching xorg-inputproto
--->  Attempting to fetch inputproto-2.0.1.tar.bz2 from http://ykf.ca.distfiles.macports.org/MacPorts/mpdistfiles/xorg-inputproto
--->  Verifying checksum(s) for xorg-inputproto
--->  Extracting xorg-inputproto
--->  Configuring xorg-inputproto
--->  Building xorg-inputproto
--->  Staging xorg-inputproto into destroot
--->  Installing xorg-inputproto @2.0.1_0
--->  Deactivating xorg-inputproto @2.0_0
--->  Cleaning xorg-inputproto
--->  Activating xorg-inputproto @2.0.1_0
--->  Cleaning xorg-inputproto
--->  Computing dependencies for xorg-libXdmcp
--->  Fetching xorg-libXdmcp
--->  Attempting to fetch libXdmcp-1.1.0.tar.bz2 from http://ykf.ca.distfiles.macports.org/MacPorts/mpdistfiles/xorg-libXdmcp
--->  Verifying checksum(s) for xorg-libXdmcp
--->  Extracting xorg-libXdmcp
--->  Configuring xorg-libXdmcp
--->  Building xorg-libXdmcp
--->  Staging xorg-libXdmcp into destroot
--->  Computing dependencies for xorg-libXdmcp
--->  Installing xorg-libXdmcp @1.1.0_0
--->  Deactivating xorg-libXdmcp @1.0.3_0
--->  Cleaning xorg-libXdmcp
--->  Activating xorg-libXdmcp @1.1.0_0
--->  Cleaning xorg-libXdmcp
--->  Computing dependencies for libxml2
--->  Fetching libxml2
--->  Attempting to fetch libxml2-2.7.8.tar.gz from http://ykf.ca.distfiles.macports.org/MacPorts/mpdistfiles/libxml2
--->  Verifying checksum(s) for libxml2
--->  Extracting libxml2
--->  Configuring libxml2
Error: The file /opt/local/lib/libz.dylib does not exist, though it was
Error: expected to have been provided by one of libxml2's dependencies. Try
Error: rebuilding the port that should have provided that file by running
Error: 
Error:     sudo port -n upgrade --force <portname>
Error: 
Error: Target org.macports.configure returned: missing required file
Log for libxml2 is at: /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_ports_textproc_libxml2/main.log
Error: Unable to upgrade port: 1
Error: Unable to execute port: upgrade xorg-libXaw failed
To report a bug, see <http://guide.macports.org/#project.tickets>