Blocked package conflict (pillow/imaging)

muzer@muzer-think ~ $ sudo emerge -DavNu world

These are the packages that would be merged, in order:

Calculating dependencies... done!
[ebuild     U  ] net-misc/rsync-3.0.9-r3 [3.0.9-r2] USE="acl iconv ipv6 xattr -static" 0 kB
[ebuild     U  ] sys-process/at-3.1.13-r2 [3.1.13-r1] USE="pam (-selinux)" 0 kB
[ebuild  N     ] dev-python/pillow-2.0.0-r1  USE="doc examples jpeg lcms scanner tiff tk truetype zlib {-test} -webp" PYTHON_TARGETS="python2_7 python3_2 -python2_6 (-python3_3)" 1,376 kB
[ebuild     U  ] virtual/python-imaging-2 [1] USE="tk" PYTHON_TARGETS="python2_7 python3_2* -python2_6 (-python3_3)" 0 kB
[ebuild     U  ] app-text/calibre-1.2 [1.1] USE="udisks" 28,958 kB
[blocks B      ] dev-python/pillow ("dev-python/pillow" is blocking dev-python/imaging-1.1.7-r2)
[blocks B      ] dev-python/imaging ("dev-python/imaging" is blocking dev-python/pillow-2.0.0-r1)

Total: 5 packages (4 upgrades, 1 new), Size of downloads: 30,334 kB
Conflict: 2 blocks (2 unsatisfied)

 * Error: The above package list contains packages which cannot be
 * installed at the same time on the same system.

  (dev-python/pillow-2.0.0-r1::gentoo, ebuild scheduled for merge) pulled in by
    dev-python/pillow[tk?,python_targets_python2_6(-)?,python_targets_python2_7(-)?,python_targets_python3_2(-)?,python_targets_python3_3(-)?,-python_single_target_python2_6(-),-python_single_target_python2_7(-),-python_single_target_python3_2(-),-python_single_target_python3_3(-)] (dev-python/pillow[tk,python_targets_python2_7(-),python_targets_python3_2(-),-python_single_target_python2_6(-),-python_single_target_python2_7(-),-python_single_target_python3_2(-),-python_single_target_python3_3(-)]) required by (virtual/python-imaging-2::gentoo, ebuild scheduled for merge)

  (dev-python/imaging-1.1.7-r2::gentoo, installed) pulled in by
    dev-python/imaging required by (net-print/hplip-3.12.10a::gentoo, installed)


For more information about Blocked Packages, please refer to the following
section of the Gentoo Linux x86 Handbook (architecture is irrelevant):

http://www.gentoo.org/doc/en/handbook/handbook-x86.xml?full=1#blocked

muzer@muzer-think ~ $