if [ "${PYTHON_SLOT_VERSION}" = 'VIRTUAL' ] ; then RDEPEND="virtual/python" python='python' elif [ "${PYTHON_SLOT_VERSION}" != '' ] ; then RDEPEND="=dev-lang/python-${PYTHON_SLOT_VERSION}*" python="python${PYTHON_SLOT_VERSION}" else RDEPEND="=dev-lang/python-2.1.3*" python='python2.1' fi is broken behaviour as it doesn't work with portage's cache mechanism. Portage variables can't be assigned conditionally if the condition depends on the local environment.
currently i don't see a possibility to change that, but with zope 2.7 there will be no problems with python anymore since it will work with the latest version
As I said, it doesn't work at all right now, it will always RDEPEND on python-2.1.3 unless the user manually deletes the cache entries for zope.
the new ebuilds >=net-zope/zope-2.7.1 don't have that problem anymore