I tried to re-compile Sakai with Pluto 1.1.4 and apparently an API changed:
/Users/csev/dev/sakai/portal/portal-render-impl/impl/src/java/org/sakaiproject/portal/render/portlet/services/SakaiPortalCallbackService.java:128: org.sakaiproject.portal.render.portlet.services.SakaiPortalCallbackService.SakaiPortletURLProvider is not abstract and does not override abstract method isSecureSupported() in org.apache.pluto.spi.PortletURLProvider
class SakaiPortletURLProvider implements PortletURLProvider
Probably no big deal – just part of the Pluto QA.