Comment 3 for bug 158743

It turned out, import of zope.app.securitypolicy failed because it couldn't import ZopeMessageFactory from zope.i18nmessageid. The problem was that zope.app.securitypolicy wasn't stating that it needed a newer version of zope.i18nmessageid (3.4.2 or higher). Instead it was accepting any version, including the one in the Grok KGS. zope.app.securitypolicy 3.4.6 now specifies the dependency correctly, so if you're not using zope.i18nmessageid 3.4.2 or higher, you'll rightfully get a version conflict from buildout instead of the cryptic ImportError when trying to run the app.