install (or build) ports system on OSX 10.7, then get permission errors on "port install anything"

[creon.levit@…]

This happens to me after installing macports binary .dmg, as well as after successfully building macports from source. It happens no matter what package I try to install:

$ uname -a
Darwin wdyn-n233-241-187.arc.nasa.gov 11.0.0 Darwin Kernel Version 11.0.0: Sat Jun 18 12:56:35 PDT 2011; root:xnu-1699.22.73~1/RELEASE_X86_64 x86_64

$ sudo port -d install atlas
DEBUG: Changing to port directory: /opt/local/var/macports/sources/rsync.macports.org/release/tarballs/ports/math/atlas
DEBUG: OS darwin/11.0.0 (Mac OS X 10.7) arch i386
DEBUG: org.macports.load registered provides 'load', a pre-existing procedure. Target override will not be provided
DEBUG: org.macports.unload registered provides 'unload', a pre-existing procedure. Target override will not be provided
DEBUG: org.macports.distfiles registered provides 'distfiles', a pre-existing procedure. Target override will not be provided
DEBUG: Using group file /opt/local/var/macports/sources/rsync.macports.org/release/tarballs/ports/_resources/port1.0/group/muniversal-1.0.tcl
DEBUG: Reading variant descriptions from /opt/local/var/macports/sources/rsync.macports.org/release/tarballs/ports/_resources/port1.0/variant_descriptions.conf
DEBUG: universal variant already exists, so not adding the default one
DEBUG: Executing variant gcc44 provides gcc44
DEBUG: changing euid/egid - current euid: 0 - current egid: 0
DEBUG: egid changed to: 501
DEBUG: euid changed to: 502
DEBUG: couldn't open "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_math_atlas/atlas/work/.macports.atlas.state": permission denied
    while executing
"open $statefile a+"
    (procedure "open_statefile" line 63)
    invoked from within
"open_statefile"
    (procedure "check_variants" line 29)
    invoked from within
"check_variants activate"
    invoked from within
"$workername eval check_variants $target"
    (procedure "mportexec" line 7)
    invoked from within
"mportexec $workername $target"
Error: Unable to execute port: couldn't open "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_math_atlas/atlas/work/.macports.atlas.state": permission denied
To report a bug, see <http://guide.macports.org/#project.tickets>

[jmroot (Joshua Root)]

Looks like you might have started the build as root and now are using privilege dropping (as is the default in MacPorts 2.0). Try cleaning.

[jmroot (Joshua Root)]

Check permissions on all the parent dirs of /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_math_atlas/atlas/work/.macports.atlas.state as well. They all need to allow rx for everyone.

[jmroot (Joshua Root)]

No response; closing.